Conversion Tables,
Formulas and
Suggested Guidelines
for
Horticultural Use
Table of Contents
Table No.
Page
1. Equivalents for liquid measure (volume) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Equivalents for dry measure and weight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. Metric system conversion table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
4. Dilution of liquid pesticides at various concentrations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
5. Equivalent quantities of dry materials (wettable powders) for various volumes of water
based on recommended pounds per 100 gallons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
6. Equivalent quantities of liquid materials (emulsion concentrates, etc.) for various volumes
of water based on pints per 100 gallons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
7. Rate of application equivalent table .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
8. Fertilizer conversions for specified square feet and row areas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
9. Fertilizer weight as measured by standard pot size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
10. Element concentrations for pounds soluble fertilizer in 1000 gallons (U.S.) water . . . . . . . . . . . . . 10
11. Injection ratios and nitrogen concentrations for constant fertilization . . . . . . . . . . . . . . . . . . . . . . . 11
12. Injector calibration with a conductivity meter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
A. Peters Single Element Fertilizer Components. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
B. Peters Mixed Soluble Fertilizer Analysis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
13. Parts per million of desired nutrient to ounces of fertilizer carrier in 100 gallons of water15
(or grams in 1 liter) and vice versa .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
14. Conversion factors among electrical conductivity (EC) units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
15. Various acids to add to irrigation water for acidification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
16. Amounts of nutrient sources to combine in making various fertilizer formulas . . . . . . . . . . . . . . . . 17
17. Formulas for additional fertilizer calculations .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
18. Miscellaneous conversions used in fertilizer calculations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
19. Osmocote® controlled-release fertilizers and their release periods . . . . . . . . . . . . . . . . . . . . . . . . . 20
20. Rates in lb/yd (kg/m ) for incorporation of three of the most popular formulations
3
3
of Nutricote into greenhouse root substrates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
21. Materials, rates necessary to lower the pH level of greenhouse potting substrate 0.5 to 1.0 units . . 21
22. Approximate amount of materials required to change pH of potting mixes . . . . . . . . . . . . . . . . . . . 22
23. Dilution/conversion chart for various chemical growth regulators . . . . . . . . . . . . . . . . . . . . . . . . . . 22
24. Pre-plant fertilizer sources and rates of application .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
25. Cornell Peat-lite Mix A for seedlings, bedding plants and potted plants .. . . . . . . . . . . . . . . . . . . . . 27
26. Number of pots per bushel and per cubic yard of soil mix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
27. Number of nursery containers that can be filled from 1 yd of soil mix . . . . . . . . . . . . . . . . . . . . . .
3
29
28. Coverage estimates for perlite, peat, topsoil and straw . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
29. Plant spacing guide (greenhouse) .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
30. Plant spacing guide (field/orchard) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Landscape
31. Estimated number of plants to fill 100 ft2 bed area for square (row) and triangular (equilateral)
planting patterns using 4 to 14 inch spacing distances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
32. Number of bedding/groundcover plants required at various spacing for landscape planting . . . . . . . . .
33. Number of plants per acre at various spacings .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
34. Times required to mow or trim lawn areas .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
35. Volume of water delivered - by size of hose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
36. Cubic yards of soil needed at various depths and areas .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
37. Areas covered in square feet at various depths . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
38. Temperature conversion .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Figure No.
Page
1A-C. Formulas for calculating greenhouse volume . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
2A-C. Formulas for calculating variously-shaped areas .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
3
Conversion Tables, Formulas and
Suggested Guidelines for Horticultural Use
Bodie V. Pennisi, Gary L. Wade, Melvin P. Garber,
Paul A. Thomas and James T. Midcap
Horticulture Department
Pesticide and fertilizer recommendations often are made on a pounds-per-acre or tons-per-acre basis for
field production. However, greenhouse and nursery operators, landscape professionals and orchardists often
must convert these recommendations to smaller areas, such as row feet or square feet per tree or per pot. Pints,
cups, ounces, tablespoons and teaspoons often are the common units of measure. Metric units of measure can
further complicate conversion.
This publication is designed to help growers make these calculations and conversions and to provide other
data useful in the management, planning and operation of horticultural enterprises. A number of formulas for
calculating fertilizer application rates on a parts-per-million basis are given. Tables for fertilizer injector
calibration using a conductivity meter, as well as pre-plant application rates for various soil mix components
and amendments, also are provided. A brief explanation of how each table is used is provided.
Tables 1 through 3 help determine equivalent measures for liquid (volume) or dry (weight) chemical
substances and also converting metric to English units.
Table 1. Equivalents for liquid measure (volume)
Gallons
Quarts
Pints
Fluid
Ounces
Cupfuls
Tablespoonful
Teaspoonful
Milliliters
Liters
1
4
8
128
16
256
768
3785
3.785
-
1
2
32
4
64
192
946
0.946
-
-
1
16
2
32
96
473
0.473
-
-
-
1
c
2
6
30
0.030
-
-
-
-
1
16
48
236
0.236
-
-
-
-
-
1
3
15
0.015
-
-
-
-
-
-
1
5
0.005
-
-
-
-
-
-
-
1
0.001
4
Table 2. Equivalents for dry measure and weight
Dry measure
3 level teaspoonfuls ..... ..... ..... ..... = 1 level tablespoonful
16 level tablespoonfuls ..... ..... .....
= 1 cupful
2 cupfuls ..... ..... ..... ..... ..... .....
= 1 pint
2 pints ..... ..... ..... ..... ..... ..... .....
= 1 quart
Weight
Pounds/Ounces
Metric
220.46 pounds . . . . . . . . . . . . . . . . . . . . . . . 100 kilograms (kg)
100 pounds . . . . . . . . . . . . . . . . . . . . . . . . . . . 45.349 kilograms
2.204 pounds .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 kilogram
1.102 pounds .. . . . . . . . . . . . . . . . . . . . . . . . . . . 500 grams (g)
1 pound/16 ounces . . . . . . . . . . . . . . . . . . . . . . 453.5900 grams
8 ounces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 226.78 grams
4 ounces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113.39 grams
3.527 ounces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110 grams
2 ounces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56.70 grams
1 ounce . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28.35 grams
3/4 ounce . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21.25 grams
1/2 ounce . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14.17 grams
1/4 ounce . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.08 grams
1/8 ounce . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.54 grams
1/16 ounce . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.77 grams
1/32 ounce . . . . . . . . . . . . . . . . . . . . . . . . . . . . 885 milligrams
1/64 ounce . . . . . . . . . . . . . . . . . . . . . . . . . . . . 442 milligrams
1/128 ounce .. . . . . . . . . . . . . . . . . . . . . . . . . . . . 221 milligrams
Ounces-to-Grams
Ounces
Grams
3/8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.631
1/2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14.75
5/8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17.718
3/4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21.162
7/8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24.805
1 .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28.349
2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56.698
1/256 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.111
1/128 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.221
1/64 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.443
1/32 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.886
1/16 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.772
1/8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.544
1/4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.087
5
Table 3. Metric system conversion table
Liquid capacity
1 fluid ounce (fl oz) .......... .......... .......... = .......... .......... ..........
1 pint (pt) = 16 fl oz .......... .......... .......... = .......... .......... ..........
1 quart (qt) ......... .......... .......... .......... = .......... .......... ..........
1 gallon (gal) ......
.......... .......... .......... = .......... .......... ..........
1 liter ..... .......... .......... .......... .......... = .......... .......... ..........
1 milliliter (ml) ...... .......... .......... .......... = .......... .......... ..........
30 milliliters (ml)
473 ml
946 ml
3,785 ml
1,000 ml
1 cubic centimeter (cc)
Dry material capacity
1 ounce (avoirdupois) .......... .......... .......... = .......... .......... ..........
1 pound (lb) .......... .......... .......... .......... = .......... .......... ..........
1 kilogram (kg) ...... .......... .......... .......... = .......... .......... ..........
28.4 grams (g)
453.6 g
1,000 g = 2.2 lb
Volume
1 cubic inch (in ) .... .......... .......... .......... = .......... .......... ..........
3
1 cubic foot (ft ) .... .......... .......... .......... = .......... .......... ..........
3
1 bushel (bu) ........ .......... .......... .......... = .......... .......... ..........
1 cubic yard (yd ) .. .......... .......... .......... = .......... .......... ..........
3
16.4 milliliters (ml)
7.48 gal = 28.3 liters (l)
1.24 ft = 35.2 liters
3
21.7 bu = 765 liters
Linear
1 inch (in) ............ .......... .......... .......... = .......... .......... ..........
1 foot (ft) ............ .......... .......... .......... = .......... .......... ..........
1 yard (yd) .......... .......... .......... .......... = .......... .......... ..........
1 meter (m) ........ .......... .......... .......... = .......... .......... ..........
2.54 centimeters (cm)
30.48 cm
91.44 cm
100 cm
Area
1 square inch (in )
.......... .......... .......... = .......... .......... ..........
2
1 square foot (ft ) .. .......... .......... .......... = .......... .......... ..........
2
1 square yard (yd ) .......... .......... .......... = .......... .......... ..........
2
1 acre (a) ........ .... .......... .......... .......... = .......... .......... ..........
1 square mile (M ) .. .......... .......... .......... = .......... .......... ..........
2
6.45 square centimeters (cm )2
0.09 square meter (m )2
0.84 square meter (m )2
0.40 hectare (ha)
2.59 square kilometer (km )2
Tables 4 through 7 help determine correct application rates for various pesticides.
Table 4. Dilution of liquid pesticides at various concentrations
Amount Desired
Dilution
1 Gal
3 Gal
Gal
5 Gal
1:100
2 tbs + 2 tsp
½ cup
¾ cup + 5 tsp
1 cup + 3 tbs
1:200
4 tsp
¼ cup
6½ tbs
½ cup + 2 tbs
1:400
2 tsp
2 tbs
3 tbs
4 tbs + 2½ tsp
1:800
1 tsp
1 tbs
1 tbs + 2 tsp
3 tbs + 2½ tsp
1:1000
¾ tsp
2¼ tsp
1 tbs + 1 tsp
1 pt + ½ cup
Example: Directions call for a 1:200 dilution. To prepare 3 gal of finished product, you would need
to add ¼ cup.
6
Table 5. Equivalent quantities of dry materials (wettable powders) for various
volumes of water based on recommended pounds per 100 gallons
Recommended Rate
Water
1 lb
2 lb
lb
4 lb
5 lb
6 lb
50 gal
½ lb
1 lb
1½ lb
2 lb
2½ lb
3 lb
25 gal
4 oz
8 oz
12 oz
1 lb
1¼ lb
1½ lb
12.5 gal
2 oz
4 oz
6 oz
8 oz
10 oz
¾ lb
5 gal
3 tbs
1½ oz
2½ oz
3¼ oz
4 oz
5 oz
1 gal
1 tsp
2 tsp
1 tbs
4 tsp
5 tsp
2 tbs
Example: Directions for use specify a rate of 4 lb per 100 gal of water. To prepare 1 gal of solution
would require 4 tsp of material.
Table 6. Equivalent quantities of liquid materials (emulsion concentrates, etc.) for
various volumes of water based on pints per 100 gallons
Water
100 gal
Recommended Rate
½ pt
1 pt
2 pt
3 pt
4 pt
5 pt
50 gals
4 fl oz
8 fl oz
1 pt
1½ pt
2 pt
2½ pt
25 gals
2 fl oz
4 fl oz
8 fl oz
12 fl oz
1 pt
1¼ pt
12.5 gals
1 fl oz
2 fl oz
4 fl oz
6 fl oz
8 fl oz
10 fl oz
5 gals
1 tbs
1 fl oz
2 fl oz
2½ fl oz
3 fl oz
4 fl oz
1 gal
½ tsp
1 tsp
2 tsp
3 tsp
4 tsp
5 tsp
Example: Directions for use specify a rate of 4 pt per 100 gal of water. To prepare 5 gal of solution
would require 3 fl oz of material.
7
Table 7. Rate of application equivalent table
Rate per Acre
Rate per 1000 sq ft
Rate per 100 sq ft
LIQUID MATERIALS
1 pt
¾ tbs
¼ tsp
1 qt
1½ tbs
½ tsp
1 gal
6 tbs
2 tsp
25 gal
4b pt
½ pt
50 gal
4b qt
1 pt
100 gal
2a gal
1 qt
200 gal
4b gal
2 qt
300 gal
7 gal
3 qt
400 gal
9¼ gal
1 gal
500 gal
11½ gal
1¼ gal
DRY MATERIALS
1 lb
2½ tsp
¼ tsp
3 lb
2¼ tbs
¾ tsp
4 lb
3 tbs
1 tsp
5 lb
4 tbs
1¼ tsp
10 lb
½ cup
2 tsp
100 lb
2¼ lb
¼ lb
200 lb
4b lb
½ lb
300 lb
7 lb
¾ lb
400 lb
9¼ lb
1 lb
500 lb
11½ lb
1¼ lb
Examples: For liquid materials, 100 gal per acre is equivalent to 2a gal per 1000 ft or 1 qt per 100 ft . For dry
2
2
materials, 4 lb per acre is equivalent to 3 tbs per 1000 ft or 1 tsp per 100 ft .
2
2
8
Tables 8 through 9 help determine the correct application rates for fertilizers when nutrition
recommendations are based on fertilizer weight.
Table 8. Fertilizer conversions for specified square feet and row area
FERTILIZER RATE FOR SPECIFIC AREAS
MATERIAL GROUPED BY
APPROXIMATE WEIGHT PER
PINT
Per 10 feet of row
spaced**
Recommended
rate per acre*
lb
100 sq ft
lb
1000 sq ft
lb
10 sq ft
tbs
100 sq ft
pt
1 ft
tbs
2 ft
tbs
3 ft
cup
10 oz per pint
Sulfur or
100
0.2
2.3
1.2
0.4
1.2
2.4
0.2
Dried Blood
500
1.2
11.5
6.0
1.9
6.0
12.0
1.1
1000
2.3
23.0
12.0
3.7
-
-
--
13 oz per pint
Urea or
100
0.2
2.3
0.9
0.3
0.9
1.8
0.2
Ammonium Nitrate or
500
1.2
11.5
4.5
1.4
4.5
9.0
0.8
Ammonium Chloride
1000
2.3
23.0
9.0
2.8
-
-
-
16 oz per pint
Ammonium Phosphate or
100
0.2
2.3
0.7
0..2
0.7
1.4
0.1
Potassium Chloride or
500
1.2
11.5
3.5
1.2
3.5
7.0
0.7
Gypsum or
1000
2.3
23.0
7.0
2.3
-
-
-
Mixed Fertilizers
19 oz per pint
Calcium Nitrate or
100
0.2
2.3
0.6
0.2
0.6
1.2
0.1
Ammonium Sulfate or
500
1.2
11.5
3.0
1.0
3.0
6.0
0.6
Superphosphate
1000
2.3
23.0
6.0
2.0
-
-
-
23 oz per pint
Ground Limestone or
100
0.2
2.3
0.5
0.2
0.5
1.0
0.1
500
1.2
11.5
2.5
0.8
2.5
5.0
0.5
Potassium Sulfate
1000
2.3
23.0
5.0
1.6
-
-
-
2000
4.6
46.0
10.0
3.2
--
--
--
* Any of the materials listed in the first column can be used at the rates shown below. **High Rates, not desirable
in row fertilization, are omitted in the table.
Example: You wish to apply calcium nitrate at the rate of 500 lbs per
acre. It weighs approximately 19 oz per pt. For application to 100 ft , you need 1.2 lb or 1.0 pt.
2
9
Table 9. Fertilizer weight as measured by standard pot size
Fertilizer
Pot Size
2¼"
3"
3½"
4"
5"
6"
Ammonium nitrate
2 oz
5½ oz
9 oz
15 oz
1 lb 12 oz
2 lb 15 oz
Urea, 45-0-0
2½ oz
6 oz
9 oz
1 lb
1 lb 13 oz
3 lb
Superphosphate
2½ oz
6 oz
9½ oz
1 lb
1 lb 14 oz
3 lb 2 oz
Dusting sulfur
2½ oz
6 oz
10 oz
1 lb
1 lb 14 oz
3 lb 3 oz
Peters, 20-5-30
2½ oz
6 oz
10 oz
1 lb 1 oz
1 lb 15 oz
3 lb 3 oz
Ammonium sulfate
3 oz
7 oz
11 oz
1 lb 3 oz
2 lb 3 oz
3 lb 11 oz
Osmocote, 14-14-14
3 oz
7½ oz
12 oz
1 lb 4 oz
2 lb 5 oz
3 lb 13 oz
MagAmp, 12-62-0
3 oz
7½ oz
12 oz
1 lb 4 oz
2 lb 5 oz
3 lb 14 oz
4
Gypsum, CaSO
3 oz
8 oz
12½ oz
1 lb 5 oz
2 lb 7 oz
4 lb 1 oz
Calcium nitrate
3 oz
8 oz
12½ oz
1 lb 6 oz
2 lb 8 oz
4 lb 2 oz
Peters, 15-0-15
3½ oz
8 oz
13 oz
1 lb 6 oz
2 lb 9 oz
4 lb 5 oz
Potassium chloride
3½ oz
9 oz
14 oz
1 lb 8 oz
2 lb 12 oz
4 lb 9 oz
Sodium nitrate
4 oz
9 oz
15 oz
1 lb 9 oz
2 lb 14 oz
4 lb 13 oz
Dolomitic limestone
5½ oz
13 oz
1 lb 5 oz
2 lb 4 oz
4 lb 2 oz
6 lb 14 oz
Clay flower pots are frequently used for fertilizer measurement by greenhouse operators. The above shows average
weights of several representative fertilizers as measured by standard clay pots when level full. The 3-inch standard
is considered to contain 8 fl oz or 1 cup. Since the actual pot size varies with the manufacturer and the volume of a
given weight of fertilizer varies with moisture and compaction, deviations of 10 percent may be expected but up to
40 percent may occur.
10
Tables 10 through 14 help determine the correct application rates for fertilizers with various analysis
when nutrition recommendations are based on parts per million and fertilizer injectors are used to deliver liquid
plant fertilizer. Table 12 is designed to help growers calibrate their injectors.
Table 10. Element concentrations for pounds soluble fertilizer in 1000 gal (U.S.) water
Pounds of Fertilizer Needed
Desired
ppm
2
5
2
% Nitrogen (N)
% Phosphate (P O )
% Potash (K O)
30
25
20
15
10
20
15
10
5
25
20
15
10
300
8.3
10.0
12.5
16.7
23.0
--
--
--
--
12.0
15.0
20.0
30.0
275
7.8
9.2
11.4
15.3
23.0
--
--
--
--
11.0
13.7
18.2
27.5
250
7.3
8.4
10.2
13.9
21.8
--
--
--
--
10.0
12.5
16.7
26.2
225
6.2
7.5
9.3
12.5
18.7
--
--
--
--
9.0
11.3
15.0
22.5
200
5.6
6.7
8.4
11.1
16.7
19.2
--
--
--
8.0
10.0
13.3
20.0
175
4.9
5.8
7.3
9.7
14.6
16.8
22.4
--
--
7.0
8.8
10.7
17.5
150
4.2
5.0
6.3
8.3
12.5
14.4
19.2
28.8
--
6.0
7.6
10.0
15.0
125
3.5
4.2
5.3
7.0
10.2
12.0
16.0
24.0
48.0
5.0
6.2
8.4
12.5
100
2.8
3.4
4.2
5.6
8.3
9.6
12.6
19.2
38.4
4.0
5.0
6.7
10.0
75
2.1
2.5
3.1
4.2
6.2
7.2
9.6
14.4
28.8
3.0
3.8
5.0
7.5
50
1.4
1.7
2.1
2.8
4.2
4.8
6.4
9.6
19.2
2.0
2.5
3.4
5.0
25
0.7
0.9
1.1
1.4
2.1
2.4
3.2
4.8
9.6
1.0
1.3
1.7
2.5
Example: You wish to apply 200 ppm N using a 20-10-20 soluble fertilizer. Reading across from 200 ppm under
the 20 percent N column, you find 8.4 lb are needed for 1000 gal water.
NOTES: 1 oz/2 gal is about 30 lb/1000
gal; 1 oz/3 gal is about 20 lb/100 gal; 1 oz/5 gal is about 12 lb/1000 gal. 1 oz/gal = 7490 ppm; 1 oz/100 gal = 75
ppm. To determine parts per million (ppm) of an element in a fertilizer, simply multiply the percent of that element
by 75. The answer will be the ppm of the element per oz of the fertilizer in 100 gal of water. As an example,
ammonium sulfate contains approximately 20 percent nitrogen. Twenty percent multiplied by 75 is 15, which is the
ppm of nitrogen in 1 oz of ammonium sulfate per 100 gal of water.
11
Table 11. Injection ratios and nitrogen concentrations for constant fertilization1
oz fertilizer per gal concentrate
oz fertilizer per gal concentrate
Ratio
100 ppm N
150 ppm N
200 ppm N
Ratio
100 ppm N
150 ppm N
200 ppm N
30% N formula
20% N formula
a
c
1:300
13.5
20.2
27.0
1:300
20.2
30.3
40.5
1:200
9.0
13.5
18.0
1:200
13.5
20.2
27.0
1:150
6.7
10.1
13.5
1:150
10.1
15.1
20.2
1:128
5.7
8.6
11.5
1:128
8.6
12.9
17.2
1:100
4.5
6.7
9.0
1:100
6.7
10.1
13.5
1:50
2.2
3.3
4.5
1:50
3.3
5.0
6.7
1:30
13
2.0
2.7
1:30
2.0
3.0
4.0
1:24
1.0
1.6
2.1
1:24
1.6
2.4
3.2
1:15
0.67
1.0
1.3
1:15
1.0
1.5
2.0
25% N formula
15% N formula
b
d
1:300
16.5
24.7
33.0
1:300
27.0
40.5
54.0
1:200
11.0
16.5
22.0
1:200
18.0
27.0
36.0
1:150
8.2
12.3
16.5
1:150
13.5
20.2
27.0
1:128
7.0
10.5
14.0
1:128
11.5
17.2
23.0
1:100
5.5
8.2
11.0
1:100
9.0
13.5
18.0
1:50
2.7
4.1
5.5
1:50
4.5
6.7
9.0
1:30
1.6
2.4
3.3
1:30
2.7
4.0
5.4
1:24
1.3
1.9
2.6
1:24
2.1
3.2
4.3
1:15
0.82
1.2
1.6
1:15
1.3
2.0
2.7
From Ball RedBook, 16 Edition, published by Ball Publishing. Reprinted with permission
1
th
e.g, 30-10-10
a
e.g., 25-5-20, 25-10-10, 25-0-25
b
e.g., 20-20-20, 20-5-30, 21-7-7
c
e.g., 15-15-15, 15-30-15, 16-4-12
d
12
Table 12. Injector calibration with a conductivity meter1
A. Peters Single Element Fertilizer Components
ppm
Nitrogen
Ammonium Nitrate
4
3
- NH NO
34% N
Ammonium Sulfate
4
2
4
(NH ) SO
21% N
Sodium Nitrate
3
NaNO
16% N
Potassium
3
Nitrate - KNO
14% N
Calcium Nitrate
3
2
Ca(NO )
15.5% N
Epsom Salt
4
MgSO
10% Mg
50
0.23
0.45
0.43
0.48
0.37
0.38
75
0.35
0.68
0.65
0.71
0.55
0.56
100
0.46
0.90
0.86
0.95
0.74
0.75
125
0.58
1.13
1.08
1.18
0.92
0.94
150
0.69
1.35
1.29
1.42
1.11
1.13
175
0.81
1.58
1.51
1.66
1.30
1.31
200
0.92
1.90
1.72
1.90
1.48
1.50
225
1.04
2.03
1.94
2.14
1.66
1.69
250
1.15
2.25
2.15
2.37
1.85
1.88
275
1.27
2.48
2.37
2.61
2.04
2.06
300
1.38
2.70
2.58
2.85
2.22
2.25
350
1.61
3.15
3.01
3.32
2.59
2.63
400
1.84
3.60
3.44
3.80
2.96
3.00
450
2.07
4.05
3.87
4.27
3.33
3.38
500
2.30
4.50
4.30
4.75
3.70
3.75
550
2.53
4.95
4.73
5.22
4.07
4.13
600
2.76
5.40
5.16
5.70
4.44
4.50
650
2.99
5.85
5.59
6.17
4.81
4.88
700
3.22
6.30
6.02
6.65
5.18
5.25
750
3.45
6.75
6.45
7.12
5.50
5.63
800
3.68
7.20
6.88
7.60
5.92
6.00
850
3.91
7.65
7.31
8.07
6.29
6.38
900
4.14
8.10
7.74
8.55
6.66
6.75
950
4.37
8.55
8.17
9.02
7.03
7.13
1000
4.60
9.00
8.60
9.50
7.40
7.50
Adapted from Grace Horticultural Products. W.R. Grace & Co. Cambridge, Massachusetts 02140.
1
NOTES:
1) For use with meters in millimhos with Peters® Single Element Fertilizer Components.
2) These are readings made with distilled water.
3) Test your plain irrigation water first and subtract that reading from the fertilizer-injected water. For
example, your water test indicates 0.5 mmhos and you are applying 500 ppm N with calcium nitrate. Your
calibration reading is 3.70 - 0.5 = 3.20 mmhos.
13
B. Peters Mixed Soluble Fertilizer Analysis
ppm
N
20-20-20
20-19-18 20-10-15
20-5-30
25-5-20
25-10-10
30-10-10
5-11-26
Hydrosol
15-16-17
15-11-29
15-20-25
15-15-15 15-10-30 15-30-15 15-0-15
16-4-12
21-7-7
Acid
21-7-7
Neutral
50
0.23
0.31
0.22
0.12
0.09
1.00
0.32
0.30
0.32
0.31
0.36
0.32
0.28
0.21
75
0.34
0.47
0.33
0.18
0.14
1.50
0.48
0.46
0.51
0.47
0.55
0.48
0.42
0.32
100
0.45
0.62
0.44
0.24
0.18
2.00
0.65
0.62
0.70
0.62
0.74
0.64
0.56
0.42
125
0.56
0.78
0.56
0.30
0.23
2.50
0.82
0.79
0.87
0.78
0.94
0.81
0.70
0.53
150
0.68
0.93
0.69
0.36
0.27
3.00
1.00
0.96
1.50
0.93
1.15
0.98
0.84
0.63
175
0.79
1.09
0.81
0.43
0.32
3.50
1.20
1.13
1.23
1.09
1.35
1.14
0.98
0.74
200
0.90
1.24
0.94
0.51
0.36
4.00
1.40
1.30
1.41
1.24
1.55
1.31
1.12
0.84
225
1.01
1.40
1.07
0.57
0.41
4.50
1.56
1.47
1.59
1.40
1.72
1.47
1.26
0.95
250
1.13
1.55
1.20
0.62
0.47
5.00
1.72
1.65
1.78
1.55
1.90
1.62
1.40
1.05
275
1.24
1.71
1.32
0.71
0.51
5.50
1.91
1.82
1.95
1.71
2.09
1.81
1.54
1.16
300
1.35
1.86
1.43
0.80
0.54
6.00
2.10
1.98
2.12
1.86
2.28
2.00
1.68
1.26
350
1.58
2.17
1.66
0.92
0.64
6.50
2.45
2.31
2.45
2.17
2.64
2.29
1.96
1.47
400
1.80
2.48
1.90
1.04
0.74
7.00
2.80
2.65
2.78
2.48
3.00
2.58
2.24
1.68
450
2.03
2.79
2.15
1.18
0.85
7.50
3.15
2.98
3.12
2.79
3.34
2.93
2.52
1.89
500
2.25
3.10
2.40
1.32
0.96
8.00
3.50
3.25
3.46
3.10
3.68
3.28
2.80
2.10
550
2.48
3.41
2.61
1.45
1.06
-
3.84
3.55
3.76
3.41
3.98
3.57
3.08
2.31
600
2.70
3.72
2.82
1.58
1.16
-
4.18
3.85
4.06
3.72
4.28
3.86
3.36
2.52
650
2.93
4.03
3.03
1.71
1.26
-
4.52
4.15
4.36
4.03
4.58
4.15
3.64
2.73
700
3.15
4.34
3.24
1.84
1.36
-
4.80
4.45
4.66
4.34
4.88
4.44
3.92
2.94
750
3.38
4.65
3.45
1.98
1.46
-
5.20
4.75
4.95
4.65
5.20
4.72
4.20
3.15
800
3.60
4.96
3.66
2.11
1.56
-
5.54
5.05
5.25
4.96
5.50
4.98
4.48
3.36
850
3.83
5.27
3.87
2.24
1.66
-
5.88
5.35
5.55
5.27
5.80
5.24
4.76
3.57
900
4.05
5.58
4.08
2.37
1.76
-
6.22
5.65
5.85
5.58
6.10
5.50
5.04
3.78
950
4.28
5.89
4.29
2.50
1.86
-
6.56
5.95
6.15
5.89
6.40
5.76
5.32
3.99
1000
4.50
6.20
4.5
2.63
1.96
-
6.90
6.25
6.45
6.20
6.70
6.00
5.60
4.20
NOTES: 1) For use with meters in millimhos with Peters® Fertilizer formulations. 2) These readings are made with distilled water. 3) Test your
plain irrigation water first and subtract that reading from the fertilizer-injected water. For example, your water test indicates 0.2 mmhos and you
are applying 200 ppm N with 15-15-15 fertilizer. Your calibration reading is 1.30 - 0.2 = 1.10 mmhos.
14
Table 13. Parts per million of desired nutrient to ounces of fertilizer carrier in 100 gallons of water (or grams in 1 liter)
and vice versa1
Ounces of Fertilizer
Carrier in 100 Gallons
Percentage of Desired Nutrient in Fertilizer Carrier
12
13
14
15.5
16
20
20.5
21
33
44
45
53
60
62
1
9
9.7
10.5
11.6
12.0
15.0
15.3
15.7
24.7
32.9
33.7
39.7
44.9
46.4
2
18
19.5
21.0
23.2
24.0
29.9
30.7
31.4
49.4
65.9
67.4
79.3
89.8
92.0
3
27
29.3
31.4
35.0
35.9
44.9
46.0
47.2
74.1
98.8
101.0
117.0
134.7
139.2
4
36
38.9
41.9
46.4
47.9
59.9
61.4
62.9
98.8
131.7
134.7
158.7
179.6
185.6
6
54
58.4
62.9
70.0
71.9
89.9
92.1
94.3
148.2
197.6
202.1
238.0
269.4
278.4
8
72
77.8
83.8
92.8
95.8
119.7
122.7
125.7
197.6
263.4
269.4
317.3
359.2
371.2
16
144
155.7
167.7
185.6
191.7
239.5
245.5
251.5
395.2
526.9
538.9
634.6
718.5
742.4
24
216
233.5
251.5
278.4
287.5
359.2
368.2
377.2
592.7
790.3
808.3
952.0 1077.7 1113.6
32
288
311.4
335.4
371.3
383.4
479.0
490.9
502.9
790.3 1053.7 1077.7 1269.3 1436.9 1484.8
40
359
389.2
419.2
464.0
479.2
598.7
613.7
628.6
987.9 1317.2 1347.1 1586.6 1796.2 1856.1
48
431
467.0
503.0
556.8
575.0
718.5
736.4
754.4 1185.5 1580.6 1616.5 1903.9 2155.4 2227.2
56
503
544.7
586.9
649.7
670.9
838.2
859.2
880.1 1383.0 1844.0 1886.0 2221.2 2514.6 2598.4
64
575
622.7
670.7
742.4
766.7
958.0
981.9 1005.8 1580.6 2107.5 2155.4 2538.6 2873.9 2969.7
Grams of Fertilizer Carrier
in 1 Liter
ppm
0.1
12
13
14
16
16
20
20.5
21
33
44
45
53
60
62
0.2
24
26
28
31
3
40
41.0
42
66
88
90
106
120
124
0.3
36
39
42
47
48
60
61.5
63
99
132
135
159
180
186
0.4
48
52
56
62
64
80
82.0
84
132
176
180
212
240
248
0.6
72
78
84
93
96
120
123.0
126
198
264
270
318
360
372
0.8
96
104
112
124
128
160
164.0
168
264
352
360
424
480
496
1.0
120
130
140
155
160
200
205.0
210
330
440
450
530
600
620
1.5
180
195
210
233
240
300
307.0
315
495
660
675
795
900
930
2.0
240
260
280
310
320
400
410.0
420
660
880
900
1060
1200
1240
2.5
300
325
350
388
400
500
512.5
525
825
1100
1125
1325
1500
1550
3.0
360
390
420
465
480
600
615.0
630
990
1320
1350
1590
1800
1860
3.5
420
455
490
543
560
700
717.5
735
1155
1540
1575
1855
2100
2170
4.0
480
520
560
620
640
800
820.0
840
1320
1760
1800
2120
2400
2480
From Nelson, P.V. 1998. Greenhouse Operations and Management, 5 ed. Published by Prentice Hall, Inc. Reprinted with permission.
1
th
15
Table 14. Conversion factors among electrical conductivity (EC) units1
From
To
Multiply by:
mmhos/cm or mS/cm or dS/cm
mhos x 10 /cm
100
-5
mhos x 10 /cm
mmhos/cm or mS/cm or dS/cm
0.01
-5
mmhos/cm or mS/cm or dS/cm
µmhos or mhos x 10
1000
-6
µmhos or mhos x 10
mmhos/cm or mS/cm or dS/cm
0.001
-6
mmhos/cm or mS/cm or dS/cm
ppm
6702
ppm
mmhos/cm or mS/cm or dS/cm
0.00149252
mhos x 10 /cm
ppm
6.70
-5
2
ppm
mhos x 10 /cm
0.14925
-5
2
µmhos or mhos x 10
ppm
0.670
-6
2
ppm
µmhos or mhos x 10
1.4925
-6
2
Adapted from T.J. Cavins, et al., 2000.
1
Some labs report EC in terms of ppm or cnvert EC to ppm. Although 670 is the basis used in this
2
example, the conversion factor can vary between 640 and 700. This conversion factor is an
average due to the variability in the type of fertilizer salts that contribute to the substrate EC in
each sample, and it should be considered a broad approximation. Expressing EC in terms of mS/cm
or mhos/cm is the preferred method.
16
Table 15 is designed to help growers decide which acid to add and in what quantities to acidify their
irrigation water.
Table 15. Various acids to add to irrigation water for acidification1
Note: The table is an example from software called
Alkalinity Calculator, available at
www.ces.ncsu.edu/depts/hort/floriculture/software/alk.html It is an acidification analysis done on a water sample
3
with a starting pH of 8.0 and alkalinity of 200 ppm CaCO acidified to an end point pH of 5.8. For your specific water
sample, download the
Alkalinity Calculator and follow the directions listed on the website. You will need to obtain a
water report on your irrigation water
prior to running the software. You will need to know the water pH and alka-
linity of your sample and have an idea about what end-point pH you want to obtain after acidification. The software
also gives you information about the cost of the acidification treatment.
Alternative Acids to Add to Irrigation Water
Acids: Phosphoric
Acid (75%)
Phosphoric
Acid (85%)
Sulfuric Acid
(35%)
Sulfuric Acid
(93%)
Nitric Acid
(61.4%)
Nitric Acid
(67%)
Amounts
For Small Volumes
ml per liter
0.253
0.207
0.348
0.087
0.234
0.209
fl oz per gallon
0.032
0.027
0.044
0.011
0.030
0.027
ml per gallon
0.956
0.785
1.316
0.330
0.884
0.793
For a 1:100 Injector
fl oz per gallon (conc.)
3.23
2.65
4.45
1.12
2.99
2.68
ml per gallon (conc.)
95.63
78.47
131.59
32.98
88.40
79.28
For a 1:128 Injector
fl oz per gallon (conc.)
4.14
3.40
5.70
1.43
3.83
3.43
ml per gallon (conc.)
122.41
100.44
168.44
42.22
113.16
101.48
For a 1:200 Injector
fl oz per gallon (conc.)
6.47
5.31
8.90
2.23
5.98
5.36
ml per gallon (conc.)
191.27
156.94
263.19
65.97
176.81
158.56
Nutrients Added by Each Type of Acid
Nutrients Added:
Phosphorus
Phosphorus
Sulfur
Sulfur
Nitrogen
Nitrogen
Amount Added (ppm):
94.6
94.6
50.3
50.3
43.7
43.7
Use the information above for modifying your fertility program.
Tables 16 through 20 help determine which fertilizers to use based on chemical analysis, reaction in
substrate, longevity in substrate (slow release fertilizers), and incorporation rates for some popular slow release
fertilizers. Tables 17 and 18 are specifically designed to provide detailed information on fertilizer calculations,
which also aid determine correct application rates.
17
Table 16. Amounts of nutrient sources to combine in making various fertilizer formulas1
Nutrient Sources2
Fertilizer Name
Analysis
33-0-013-0-4415.5-0-016.0.021-0-045-0-00-0-6012-62-021-53-0% of N as
4
NH + Urea
Reaction in
Substrate4
Ammonium nitrate
33-0-0
X
50
A
Potassium nitrate
13-0-44
X
0
N
Calcium nitrate
15.5-0-0
X
6
B
Sodium nitrate
16-0-0
X
0
B
Ammonium sulfate
21-0-0
X
100
A
Urea
45-0-0
X
100
SA
Potassium chloride
0-0-60
X
-
N
Monoammonium phosphate
12-62-0
X
100
A
Diammonium phosphate
21-53-0
X
100
SA
3
Magnesium nitrate
10-0-0
0
B
Chrysanthemum green
18-0-22
1
2
1
47
A
General Summer
20-10-24
1
1
2
1
83
A
General low phosphate
21-4-20
7
4
1
55
A
General summer
21-17-20
1
2
3
3
90
A
General
17-6-27
4
4
1
57
A
UConn Mix
19-5-24
6
2
2
1
49
N
Editor��s favorite
20-5-30
13
4
2
57
SA
20-20-20 substitute
20-20-22
4
1
3
67
SA
Starter and pink hydrangea
12-41-15
1
2
65
SA
Starter and pink hydrangea
17-35-16
1
4
10
100
SA
N-K only
16-0-24
2
1
2
40
SA
N-K only
20-0-30
1
2
28
SA
Blue hydrangea
13-0-22
2
1
100
VA
Blue hydrangea
15-0-15
3
1
100
VA
Acid
21-9-9
3
1
7
1
2
79
VA
Spring carnation
10-0-17
5
2
0
B
Winter nitrate
15-0-15
1
2
5
B
Winter potash
15-0-22
1
1
4
B
Lily substitute
16-4-12
1
4
6
1
22
N
High K
15-10-30
7
1
2
28
N
From Nelson, P.V. 1998. Greenhouse Operations and Management, 5 ed. Published by Prentice Hall, Inc. Reprinted with permission.
1
th
For names of nutrient sources, see the first nine entries in the Name column.
2
Diammonium phosphate may be pelletized and coated. To dissolve, use very hot water and stir vigorously. Sediment formation should not cause
3
concern. Use crystalline potassium chloride if possible.
B = basic; N = neutral; SA = slightly acid; A = acid; VA = very acid.
4
NOTE: For example, an 18-0-22 formula fertilizer can be formulated by blending together 1 lb of ammonium nitrate plus 2 lbs of potassium nitrate
plus 1 lb of ammonium sulfate. This formulation is determined by locating the 18-0-22 formula in the Analysis column. Then the three numbers 1, 2
and 1 are located in the row after this formula. Each of the three numbers is traced to the X above it and then to the nutrient source to the left of the
X.
18
Table 17. Formulas for additional fertilizer calculations
Compound
Formula
Formula Weight
4
3
Ammonium Nitrate
NH NO
80.8
4 2
4
Ammonium Sulfate
(NH ) SO
132.0
3 2
Calcium Nitrate
Ca(NO )
164.0
3
Potassium Nitrate
KNO
101.1
Potassium Chloride
KCl
74.6
2
4
Potassium Sulfate
K SO
174.2
2 2
Urea
CO(NH )
60.0
Element
Symbol
Atomic Weight
Calcium
Ca
40.1
Carbon
C
12.0
Chlorine
Cl
35.5
Hydrogen
H
1.0
Nitrogen
N
14.0
Oxygen
O
16.0
Phosphorus
P
31.0
Potassium
K
39.1
Using Chemicals
1) mg of fertilizer source/liter of water =
(ppm)(formula weight)
(atomic weight of element)(number of units in formula of fertilizer source)
2) ppm =
(mg of fertilizer/liter of water)(atomic weight of element)(number of units of element in formula of fertilizer source)
(formula weight of fertilizer source)
3) to convert mg/l to lbs/100 gal, multiply mg by 0.0008344
4) to convert lbs/100 gal to mg/l, divide lbs by 0.0008344
2
4
EXAMPLE:
How many pounds of potassium sulfate (K SO ) need to be dissolved in 100 gallons of water to
make 100 ppm K solution.
2
4
Get the formula weight of potassium sulfate (K SO ) and the atomic weight of potassium from
Table 14 (page 15).
Then:
2
4
1) mg of K SO / liter of water = (100 x 174.2) �� (39.1 x 2) = 222.8 mg/L
2) 222.8 mg/L x 0.00083440 = 0.186 lbs potassium sulfate/100 gal
19
Using Premixed Fertilizers
1) mg of mixed fertilizer/liter of water
= (ppm of N desired) (100)
(% N in fertilizer)
2
5
2) ppm of P
= (mg of mixed fertilizer/liter of water) (% P O ) (0.4366)
100
2
3) ppm of K
= (mg of mixed fertilizer/liter of water) (% K O) (0.8301)
100
4) mg of mixed fertilizer/liter of water
= (ppm of P desired) (100)
2
5
(% P O ) (0.4366)
5) mg of mixed fertilizer/liter of water
= (ppm of K desired) (100)
2
(% K O) (0.8301)
6) mg of mixed fertilizer/liter of water
= (mg of mixed fertilizer/liter of water) (% N)
10
Table 18. Miscellaneous conversions used in fertilizer calculations
1 millimeter or cubic centimeter of water weighs 1 gram
1 liter of water weighs 1 kilogram
1 gallon of water weighs 8.34 pounds
1 part per million (ppm)
= 0.0001 percent
1 part per million
= 1 milligram/liter
1 part per million
= 0.013 ounces in 100 gallons of water
1 percent
= 10,000 ppm
1 percent
= 10 grams per liter
1 percent
= 10,000 grams per kilogram
1 percent
= 1.33 ounces by weight per gallon of water
1 percent
= 8.34 pounds per 100 gallons of water
0.1 percent
= 1000 ppm
= 1000 milligrams per liter
0.01 percent
= 100 ppm
= 100 milligrams per liter
0.001 percent
= 100 ppm
= 10 milligrams per liter
0.0001 percent
= 100 ppm
= 1 milligram per liter
Approximate weight-volume measurements for making small volumes of water soluble fertilizers
1 cup
= 8 oz or ½ lbs of fertilizer
1 tablespoon
= 0.5 oz of fertilizer
2 cups
= 1 lb of fertilizer
2 tablespoons
= 1 oz of fertilizer
Useful conversions
1 ton/acre
= 20.8 grams/square foot
100 lbs/acre
= 0.2296 lbs/100 square feet
1 ton/acre
= 1 lb/21.78 square feet
grams/square foot x 96
= lbs/acre
1 gram/square foot
= 96 lbs/acre
lbs/square foot x 43,560
= lbs/acre
1 lb/acre
= 0.0104 g/square foot
100 square feet
= 1/435.6 or 0.002296 acres
100 lbs/acre
= 0.2296 lbs/100 square feet
Weight conversions from lbs/acre to weight/100 square feet
lbs/acre
amount applied/100 square feet
lbs/acre
amount applied/100 square feet
100
3.7 oz
700
1 lb 10 oz
200
7.4 oz
800
1 lb 13 oz
300
11.1 oz
900
2 lb 1 oz
400
14.8 oz
1000
2 lb 5 oz
500
1 lb 2½ oz
2000
4 lb 10 oz
600
1 lb 6 oz
Percent to Ratio Conversion
2.0% = 1:50
0.6% = 1:167
1.5% = 1:67
0.5% = 1:200
1.0% = 1:100
0.4% = 1:250
0.9% = 1:111
0.3% = 1:333
0.8% = 1:128
0.2% = 1:500
0.7% = 1:143
20
Table 19. Osmocote® controlled-release fertilizers and their release periods1
Analysis
Longevity (months) Product Name
2
14-14-14
3-4
Osmocote®3
19-6-12
3-4
Osmocote®3
13-13-13
8-9
Osmocote® 3
18-6-12
8-9
Osmocote® Fast Start
3
18-6-12
8-9
Osmocote®3
17-7-12
12-14
Osmocote®3
15-9-12
3-4
Osmocote® Plus
15-9-12
5-6
Osmocote® Plus
15-9-12
8-9
Osmocote® Plus
15-9-12
12-14
Osmocote® Plus
15-9-12
14-16
Osmocote® Plus
16-8-12
8-9
Osmocote® Plus Minors Tablets
19-5-8 + Minors
8-9
Osmocote® Pro with Poly-S
19-5-9 + Minors
12-14
Osmocote® Pro with Poly-S
20-5-8 + Minors
8-9
Osmocote® Pro with Poly-S
24-4-8
8-9
Osmocote® Pro with Resin Coated Urea
24-4-7
12-14
Osmocote® Pro with Resin Coated Urea
24-4-6
14-16
Osmocote® Pro with Resin Coated Urea
21-4-7w/Mg & Fe
8-9
Osmocote® Pro with Resin Coated Urea
21-3-7w/Mg & Fe
12-14
Osmocote® Pro with Resin Coated Urea
22-4-9 + Minors
5-6
Osmocote® Pro with Resin Coated Urea
22-4-8 + Minors
8-9
Osmocote® Pro with Resin Coated Urea
22-4-7 + Minors
12-14
Osmocote® Pro with Resin Coated Urea
22-4-6 + Minors
14-16
Osmocote® Pro with Resin Coated Urea
20-4-9
8-9
Osmocote® Pro with Methylene Urea and Ureaform
20-4-8
12-14
Osmocote® Pro with Methylene Urea and Ureaform
23-4-8 + Minors
14-16
Osmocote® Pro + ScottKoteTM
19-7-10 + Fe
3-4
Osmocote® Pro with Uncoated NPK and Iron
18-7-10 + Fe
8-9
Osmocote® Pro with Uncoated NPK and Iron
17-7-10 + Fe
12-14
Osmocote® Pro with Uncoated NPK and Iron
13-10-13
5-6
Osmocote® Pro with IBDU and Minors
15-10-10
8-9
Osmocote® Pro with IBDU and Minors
18-8-8
8-9
Osmocote® Pro with IBDU and Minors
20-4-8
8-9
Osmocote® Pro with IBDU and Minors
18-5-9
12-14
Osmocote® Pro with IBDU and Minors
17-6-12 + Minors
3-4
Sierra® Tablets
17-6-10 + Minors
8-9
Sierra® Tablets
From the Scotts Company and Subsidiaries, Marysville, OH 43041.
1
At an average root substrate temperature of 70 degrees F (21 degrees C).
2
Six trace elements plus magnesium.
3
21
Table 20. Rates in lb/yd (kg/m ) for incorporation of three of the most
3
3
popular formulations of Nutricote into greenhouse root substrates
Release Type
(days )
Sensitive Crops
Medium-Feeding Crops
Heavy-Feeding Crops
3
13-13-13
70
2.5
(1.5)
5
(3.0)
8.5
(5.1)
100
3.5
(2.1)
140
5
(3.0)
9
(5.4)
13
(7.8)
180
6
(3.6)
11
(6.6)
17
(10.2)
270
8
(4.8)
13
(7.8)
21
(12.6)
360
11
(6.6)
15
(9.0)
25
(15.0)
14-14-14
40
2
(1.2)
5
(3.0)
8
(4.7)
70
4
(2.4)
9
(5.4)
14
(8.3)
100
5
(3.0)
12
(7.1)
20
(11.9)
140
8
(4.7)
15
(9.0)
22
(13.0)
180
12
(7.1)
20
(11.9)
28
(16.6)
270
16
(9.5)
24
(14.2)
32
(19.0)
360
20
(11.9)
28
(16.6)
36
(21.3)
18-6-8
70
2
(1.2)
4.5
(2.7)
7.5
(4.5)
100
3
(1.8)
6.5
(3.9)
11
(6.6)
140
4.5
(2.7)
8
(4.8)
12
(7.2)
180
6
(3.6)
11
(6.6)
14
(8.4)
270
8
(4.8)
13
(7.8)
16
(12.0)
360
11
(6.6)
15
(9.0)
18
(13.8)
From Nelson, P.V. 1998. Greenhouse Operations and Management, 5 ed. Published by
1
th
Prentice Hall, Inc. Reprinted with permission.
Tables 21 through 22 are designed to assist growers in correcting the pH of the growing substrate.
Table 21. Materials and rates necessary to lower the pH level of greenhouse potting
substrate 0.5 to 1.0 units 1
Material
Pounds to incorporate
in lbs/yd3
Pounds to dissolve in
100 gal of water2
Rate of change
in pH
Aluminum sulfate
1.5
6.0
Rapid
Iron sulfate
1.5
6.0
Moderate
Finely-ground elemental sulfur
0.75
-
Slow
Adapted from Bailey, D.A. 1996.
1
Apply this drench as a normal watering, about 1 quart per square foot or 8 fluid ounces per 6-inch pot.
2
22
Table 22. Approximate amount of materials required to change pH of peat-
based potting mixes1
Pounds per cubic yard to change acidity to pH 5.7 for:
Beginning pH
50% Peat
50% Bark
100% Peat
7.5
2.0
3.4
2
7.0
1.5
2.5
6.5
1.0
2.0
5.0
2.5
3.5
3
4.5
5.6
7.4
4.0
7.9
11.5*
3.5
10.5*
15.58
Adapted from Conover, C.A., and R.T. Poole. 1984.
1
Add sulfur or acidifying mixture to lower pH to 5.7.
2
Add dolomitic lime or equivalent amount of calcium to raise pH to 5.7.
3
Addition of more than 10 pounds of dolomitic per yd can cause micro-nutrient deficiencies.
*
3
Table 23 will help when applying various plant growth regulators.
Table 23. Dilution/conversion chart for various plant growth regulators1
A-REST (0.0264% active ingredient)
Spray
Spray Solution
(ppm)
Fluid Ounces per Gallon
of Final Solution
Milliliters per Gallon of
Final Solution
Milliliters per Liter of
Final Solution
1
48
14.34
3.79
3
1.45
43.02
11.36
10
4.85
143.39
37.88
25
12.12
358.47
94.70
50
24.24
716.93
189.39
75
36.36
1075.40
284.09
100
48.48
1433.87
378.79
Drench
Dose
(Milligrams
per 6-in Pot)
Drench Volume
per 6-in Pot*
(Fluid Ounces)
ppm
solution
Fluid Ounces
per Gallon of
Final Solution
Milliliters per
Gallon of Final
Solution
Milliliters per
Liter of Final
Solution
0.125
4
1.06
0.51
15.15
4.0
0.25
4
2.11
1.02
30.30
8.01
0.50
4
4.23
2.05
60.61
16.01
0.75
4
6.34
3.07
90.91
24.02
1.00
4
8.45
4.10
121.21
32.02
* 2 fl oz/4-in pot; 3 fl oz/5-in pot; 10 fl oz/8-in pot
23
Table 23. (Continued)
CYCOCEL (11.8% active ingredient)
Spray
Spray Solution
(ppm)
Fluid Ounces per Gallon
of Final Solution
Milliliters per Gallon of
Final Solution
Milliliters per Liter of
Final Solution
1,000
1.08
32.08
8.47
1,500*
1.63
48.12
12.71
2,000
2.17
64.16
16.95
2,500
2.71
80.20
21.19
3,000**
3.25
96.24
25.42
5,000
5.42
160.40
42.37
* Commonly referred to as 1:80. ** Commonly referred to as 1:40.
Drench
Dose
(Milligrams
per 6-in Pot)
Drench Volume
per 6-in Pot*
(Fluid Ounces)
ppm
Fluid Ounces
per Gallon of
Final Solution
Milliliters per
Gallon of Final
Solution
Milliliters per
Liter of Final
Solution
355
6
2,000
2.17
64.18
16.95
532
6
3,000**
3.25
96.18
25.42
710
6
4,000
4.34
128.36
33.90
* 2 fl oz/2¼- to 3-in pot; 3 fl oz/4-in pot; 4 fl oz/5-in pot; 8 fl oz/8-in pot.
** Commonly referred to as 1:40.
B-NINE WSG (85% active ingredient)
Spray
Spray Solution
(ppm)
Ounces per Gallon of
Final Solution
Grams per Gallon of
Final Solution
Grams per Liter of
Final Solution
1,000
0.16
4.45
1.18
2,500
0.39
11.13
2.94
5,000
0.79
22.26
5.88
7,500
1.18
33.40
8.82
BONZI (0.4% active ingredient)
Spray
Spray Solution
(ppm)
Fluid Ounces per Gallon
of Final Solution
Milliliters per Gallon of
Final Solution
Milliliters per Liter of
Final Solution
1
0.032
0.95
0.25
3
0.096
2.84
0.75
5
0.160
4.73
1.25
10
0.320
9.46
2.50
15
0.480
14.20
3.75
25
0.800
23.66
6.25
45
1.440
42.59
11.25
60
1.920
56.78
15.00
90
2.880
85.17
22.50
24
Table 23. (Continued)
BONZI (cont.)
Drench
Dose
(Milligrams
per 6-in Pot)
Drench Volume
per 6-in Pot*
(Fluid Ounces)
ppm
Fluid Ounces
per Gallon of
Final Solution
Milliliters per
Gallon of Final
Solution
Milliliters per
Liter of Final
Solution
0.1
4
0.85
0.03
0.8
0.21
0.2
4
1.69
0.05
1.6
0.42
0.5
4
4.23
0.14
4.0
1.06
1.0
4
8.45
0.27
8.0
2.11
1.9
4
16.06
0.51
15.2
4.02
* 2 fl oz/4-in pot; 3 fl oz/5-in pot; 10 fl oz/8-in pot.
SUMAGIC (0.055% active ingredient)
Spray
Spray Solution
(ppm)
Fluid Ounces per Gallon
of Final Solution
Milliliters per Gallon of
Final Solution
Milliliters per Liter of
Final Solution
1
0.26
7.57
2
3
0.77
22.71
6
5
1.28
37.85
10
10
2.56
75.71
20
15
3.84
113.56
30
25
6.40
189.27
50
30
7.68
227.12
60
50
12.80
378.54
100
Drench
Dose
(Milligrams
per 6-in Pot)
Drench Volume
per 6-in Pot*
(Fluid Ounces)
ppm
Fluid Ounces
per Gallon of
Final Solution
Milliliters per
Gallon of Final
Solution
Milliliters per
Liter of Final
Solution
0.02
4
0.17
0.04
1.28
0.34
0.03
4
0.25
0.06
1.92
0.51
0.04
4
0.34
0.09
2.56
0.68
0.05
4
0.42
0.11
3.20
0.85
0.06
4
0.51
0.13
3.84
1.01
0.09
4
0.76
0.19
5.76
1.52
0.12
4
1.01
0.26
7.68
2.03
0.20
4
1.69
0.43
12.80
3.38
* 2 fl oz/4-in pot; 3 fl oz/5-in pot; 10 fl oz/8-in pot.
25
Table 23. (Cont.)
FLOREL (3.9% active ingredient)
Spray
Spray Solution
(ppm)
Fluid Ounces per Gallon
of Final Solution
Milliliters per Gallon of
Final Solution
Milliliters per Liter of
Final Solution
300
0.97
28.72
7.59
325
1.05
331.11
8.22
500
1.62
47.86
12.64
750
2.43
28.89
18.97
975
3.16
93.34
24.66
1,000
3.24
95.73
25.29
PRO-GIBB (4% active ingredient)
Spray
Spray Solution
(ppm)
Fluid Ounces per Gallon
of Final Solution
Milliliters per Gallon of
Final Solution
Milliliters per Liter of
Final Solution
2.5
0.008
0.24
0.06
5.0
0.016
0.47
0.13
100.0
0.320
9.46
2.50
250.0
0.800
23.66
6.25
300.0
0.960
28.39
7.50
500.0
1.600
47.31
12.50
FASCINATION
Spray
ppm BA/GA
Fluid Ounces per Gallon
of Final Solution
Milliliters per Gallon of
Final Solution
Milliliters per Liter of
Final Solution
1/1
0.007
0.2
0.06
5/5
0.04
1.1
0.3
10/10
0.07
2.1
0.6
25/25
0.18
5.3
1.4
50/50
0.36
10.5
2.8
75/75
0.53
15.8
4.2
100/100
0.71
21.0
5.5
Adapted from Hammer, P.A. 1992.
1
26
Tables 24 through 25 are designed to assist growers who desire to prepare their own substrate mix.
Table 24. Pre-plant fertilizer sources and rates of application 1,2
Nutrient source
Rate per cubic yard (per m )3
Soil-based media
Soilless media
To provide calcium and magnesium
When a pH rise is desired:
Dolomitic limestone
0-10 lbs (0.6 kg)
10 lbs (6 kg)
When no pH shift is desired:
Gypsum for calcium
0-5 lbs (0.3 kg)
0-5 lbs (0.3 kg)
Epsom salt for magnesium
0-1 lbs (0-0.6 kg)
0-1 lb (0-0.6 kg)
To provide phosphorus3
Superphosphate (0-45-0), or
1.5 lb (0.9 kg)
2.25 lbs (1.3 k.)
To provide sulfur
Gypsum (calcium sulfate)
1.5 lbs (0.9 kg)
1.5 lbs (0.9 kg)
To provide micronutrients: iron, manganese, zinc, copper, boron, molybdenum
Esmigran
3-6 lbs (1.8-3.6 kg)
3-6 lbs (1.8-3.6 kg)
Micromax
1-1.5 lbs (0.6-0.9 kg)
1-1.5 lb (0.6-0.9 kg)
Promax
1-1.5 lbs (0.6-0.9 kg)
1-1.5 lb (0.6-0.9 kg)
F-555HF
3 oz (112 g)
3 oz (112 g)
F-111HR
1 lb (0.6 kg)
1 lb (0.6 kg)
To provide nitrogen and potassium (optional)
Calcium nitrate, or
1 lb (0.6 kg)
1 lb (0.6 kg)
Potassium nitrate
1 lb (0.6 kg)
1 lb (0.6 kg)
From Nelson, P.V. 1998.
Greenhouse Operations and Management, 5 ed. Published by
1
th
Prentice Hall, Inc. Reprinted with permission.
Rates in this table are for crops other than seedlings. Only limestone is necessary in
2
seedling substrates. Optional nutrient sources for seedling substrate include up to 1 lb
(0.6 kg) each of superphosphate, gypsum, and calcium nitrate; no potassium nitrate;
and the low end of the rate range for micronutrients.
These are maximum rates designed to supply phosphorus for three to four months if pH
3
is maintained in a desirable range for the crop and the leaching percentage is at or below
20 percent.
27
Table 25. Cornell Peat-Lite Mix A for seedlings, bedding plants
and potted plants*
Materials Used
Amount per
Cubic Yard
Amount per Bushel
1
Spagnum peat moss
0.5 cubic yard
(13 bushels)
0.5 bushel
Horticultural grade vermiculite
#2 size for seed germination
#2 or 3 for transplanting
0.5 cubic yard
(13 bushels)
0.5 bushel
Superphosphate
1 to 2 pounds
20.5 to 41.0 grams
(1 to 2 tablespoons)
or
Treble superphosphate
0.5 to 1 pound
2
10.3 to 20.5 grams
(0.6 to 1.2 tablespoons)
Ground dolomitic limestone
5 to 10 pounds
103 to 206 grams
2
(5.2 to 10.4 tablespoons)
Gypsum
2.0 pounds
41 grams
2
(2.5 tablespoons)
Calcium nitrate
0.5 pound
10 grams
(1.2 tablespoons)
Potassium nitrate
0.5 pound
10 grams
(1.2 tablespoons)
Trace element material (Use Only One)
Esmigran, or
4.0 pounds
81 grams
(4.0 tablespoons)
Micromax
1.5 pounds
31 grams
(1.7 tablespoons)
Wetting agent (Use Only One )3
Aqua-Gro 2000 granular
or
1.0 pound
----
Aqua-Gro 2000-L liquid
3-5 fluid ounces
0.5 level teaspoon
4
PsiMatric liquid
2-4 fluid ounces
0.5 level teaspoon
5
A cubic yard equals 27 cubic feet or approximately 22 bushels. A 15 to 20 percent
1
shrink occurs in mixing. Therefore, an additional 5 cubic feet or 4 bushels are used to
obtain a full cubic yard.
If treble superphosphate is used, gypsum is added to supply sulphur. If only 5 pounds
2
of limestone are used for pH control, then add the gypsum that supplied calcium and
sulphur.
The granular Aqua-Grow is preferred.
3
3 ounces/yard for germination/seedlings, 5 ounces/yard for bedding plants and pot
4
plants.
2 ounces/yard for germination/seedlings, 4 ounces/yard for bedding plants and pot
5
plants.
* Adapted from Fonteno. W.C. 1994
28
Table 26. Number of pots and flats that can be filled from 1 ft of soil mix
3
Pot Size
(in)
Approximate Dimension
Top x Depth x Bottom
(in)
Number of
Pots/ft
Type
3
Approximate Dimension
Top x Depth x Bottom
(in)
Units/ft3
Standard Round Pots
Flats
16
2¼
2¼ x 2 /
x 1¾
256
Germination tray
11½ x 21¼ x 1c
7.0
1
2½
2d x 2¼ x 2
208
20-row Seeding
tray
11½ x 21¼ x 1c
11.0
16
3
3 x 2 / x 2¼
120
Standard Cell-Packs
13
10
3½
3d x 3 / x 2d
80
8-4 cell packs per tray
5.4
3
4
4 x 3f x 2¾
48
8-6 cell packs per tray
5.9
4½
4d x 4d x 3
40
10-4 cell packs per tray
6.2
5
5 x 3½ x 4
28
10-6 cell packs per tray
6.7
16
5½
5½ x 5d x 3 /
20
12-4 cell packs per tray
6.0
13
16
6
6 x 5¾ x 4 /
16
12-6 cell packs per tray
7.0
1
16
7
6¾ x 7¾ x 4 /
10
Standard size 11¼ x 21¼ x 2½
11
8
7e x 7¾ x 5d
6
Plug Flats
10
9f x 9¾ x 6f
3
50 sq. flat
1f x 2¼
6.3
16
Azalea Pots
72 rd. flat
1 / x 1¾
12.8
7
16
16
16
4
4 x 21 / x 3
56
72 sq. flat
1 / x 2 /
7.3
3
9
3
16
4½
4½ x 3d x 3¼
44
98 sq. flat
1 / x 2
7.9
5
16
16
16
16
5
5 x 3 / x 3 /
28
128 sq. flat
1 / x 1 /
9.0
13
9
3
13
5½
5½ x 4¼ x 3f
24
162 sq. flat
1 x 1½
9.2
16
6
6 x 4e x 4¼
18
200 sq. flat
/ x 1½
10.7
5
16
6½
6½ x 5 x 4 /
16
273 sq. flat
¾ x 1c
18.6
9
16
16
76
f x 5d x 5 /
12
288 rd. flat
/ x 1
19.1
1
13
16
16
7½
7d x 5 / x 5d
10
288 sq. flat
/ x 1¼
15.0
11
13
8
8c x 5f x 6
7
392 sq. flat
e x f
23.1
8½
8c x 6¼ x 6¼
6
406 sq. flat
e x f
22.2
16
10
9f x 7d x 7¼
4
512 sq. flat
/ x ¾
24.7
9
Square Pots
Nursery Containers (plastic)
16
2¼
/ x 1f x 1½
357
1 gal
6½ x 6½
10.0
15
16
2½
2d x 1 / x 1f
224
2 gal
8½ x 8½
4.5
15
3
2¾ x 2¼ x 2c
3 gal
10¼ x 9e
3.3
3½
3¼ x 2¾ x 2½
Saucerless
4
3e x 3c x 2f
8
9.7
4½
4c x 3e x 3¼
0
5.3
Bulb Pans
2
3.1
16
16
16
6
6 / x 3 / x 4 /
24
Hanging Baskets
1
9
9
16
16
16
7
7 / x 3 / x 5 /
16
6
6 x 4½ 3¼
29
1
13
9
16
16
10
10¼ x 4 / x 8c
5
8
7 ½ x 4f x 4 /
11
15
1
12
12c x 6 x 9¾
3
10
10 x 6c x 4
5
29
Table 26. (Continued)
Geranium Pots
NOTES: Sources – Eason Horticultural Resources, Inc.,
Crestview Hills, KY, and Hummert��s
Helpful Hints, 1999-2000 edition.
These figures have to be treated as approximations. Actual
pot dimensions will vary from one manufacturer to another.
Based on volume of pots when filled level to rim with loose,
unpacked soil mix.
3½
3¼ x 3 x 2d
96
16
16
4
3 / x 3 / x 2f
56
15
7
16
4¼
4¼ x 3 / x 3c
50
9
4½
4d x 3f x 3
44
Table 27. Number of nursery containers
that can be filled from 1 yd of soil mix
3
1
Size
# / per yd3
Trade 1
300
Full 1
200
2
140
3
8
0
5
5
0
7
3
5
10
20
15
14
25
8
45
4
Source: Ruter, J. (pers. communication)
1
Soil Mix Volumes
1 bushel = 1 ¼ cu. ft.
1 cu. yard = 27 cu. ft.
1 cu. yard = 22 bushels
100 sq. ft. of bench area (at 6 in. soil depth) = 50 cu. ft. or 40 bushels of soil mix.
Table 28. Coverage estimates for perlite, peat, topsoil and straw
1 Bale
Thickness
4 cu ft
Perlite
6 cu ft Canadian Peat (compressed)
(12 cu ft loose)
1 cu yd* Peat
Mulches, Topsoil, etc. Pinestraw
Wheatstraw
2 in
28 sq ft
72 sq ft
162 sq ft
90 sq ft
180 sq ft
1 in
48 sq ft
144 sq ft
324 sq ft
180 sq ft
360 sq ft
½ in
96 sq ft
288 sq ft
648 sq ft
360 sq ft
720 sq ft
¼ in
192 sq ft
576 sq ft
1296 sq ft
720 sq ft
1440 sq ft
* 1 cubic yard (yd ) = 27 cubic feet (ft )
3
3
30
Tables 29 through 30 help determine correct spacing and number of plants at each spacing for both
greenhouse and field situations.
Table 29. Plant spacing guide (greenhouse)
Spacing
Plants/sq ft
Plants/A of
production area
Plants/A of
ground covered*
8" x 9"
2.0
87,000
58,000
8" x 8"
2.3
98,000
65,000
8" x 7"
2.6
114,000
76,000
8" x 6"
3.0
30,000
87,000
6" x 7"
3.4
147,000
98,000
6" x 6"
4.0
174,000
116,000
6" x 5"
4.8
208,000
139,000
5" x 5"
5.8
252,000
168,000
5" x 4"
7.2
313,000
209,000
5" x 3"
9.6
418,000
279,000
4" x 3"
12.0
522,000
348,000
* Assuming 1/3 of production area devoted to aisles, etc.
Table 30. Plant spacing guide (field/orchard) 1
Spacing Between Plants Within the Row
Feet
6
8
10
12
14
16
18
20
22
24
26
Spacing Between Rows of Plants
4
1815
1361
1089
907
777
680
605
544
495
453
418
6
1218
907
726
605
518
453
403
363
330
302
279
8
907
680
544
453
388
339
302
272
247
226
209
10
726
544
435
362
311
272
242
218
207
181
167
12
605
453
362
302
259
226
201
181
165
151
139
14
518
388
311
259
222
194
172
155
141
129
119
16
453
339
272
226
194
169
151
136
123
113
104
18
403
302
242
201
172
151
134
121
110
100
93
20
363
272
218
181
155
136
121
108
99
90
83
22
330
247
207
165
141
123
110
99
90
82
76
24
302
226
181
151
129
113
100
90
82
75
69
26
279
209
167
139
119
104
93
83
76
69
64
Number of Plants per Acre
To determine the number of plants per acre for spacing not given in the table, multiply the distance in the row
1
by the distance between rows and divide that number into 43,560.
31
Landscape
Tables 31 through 36 are designed to aid landscape professionals and homeowners in determining
number of plants at various spacing, cubic yards of soil needed at various depths and areas, areas covered in
square feet at various depths, time needed to trim lawns, and the volume of water delivered as affected by the
size of irrigation hose.
Table 31. Estimated number of plants to fill 100 ft of bed area for square (row) and triangular
2
(equilateral) planting patterns using 4- to 14-inch spacing distances1
Planting Pattern
Inches between
rows of plants (Y)
Inches between
plants (X)
within rows
Estimated
number of plants
per 100 ft2
Square
For square spacing,
the distance between
plants within rows (x)
equals the distance
between rows (Y)
4
4
900
6
6
400
8
8
225
10
10
144
12
12
100
14
14
74
Triangular
For triangular spacing,
the distance between
plants within rows and
between rows both
equal X, and the
distance between rows
(Y) equals 0.886 X.
3.46
4
1039
5.20
6
462
6.93
8
260
8.66
10
166
10.39
12
115
12.12
14
85
Adopted from Bailey, D.A., and M.A. Powell. 1999.
1
32
Table 32. Volume of water delivered – by size of hose
Water Pressure
(lbs)
(Gallons per Minute in Bold Face)
Hose Diameter
3/8"
13/32"
7/16"
1/2"
9/16"
3/4"
5/8"
30
2.6
3.2
3.8
5.3
7.2
9.3
14.5
40
3.5
4.2
5.0
7.0
9.4
12.2
19.0
50
4.3
5.2
6.3
8.8
11.8
15.3
24.0
60
5.2
6.2
7.5
10.5
14.1
18.3
28.5
70
6.0
7.3
8.7
12.2
16.2
21.0
32.7
80
6.8
8.3
9.9
13.9
18.5
24.0
37.3
NOTE: Table based on 50-foot hose length; for 25 feet, multiply by 1.40; for 75 feet, multiply by 0.80.
Table 33. Number of plants per acre at various spacing
Distance Apart
No. of
Plants
Distance Apart
No. of
Plants
Distance Apart
No. of
Plants
3 x 3 inches
696,690
4 x 4 feet
2,722
13 x 13 feet
257
4 x 4 inches
392,040
4½ x 4½ feet
2,151
14 x 14 feet
222
6 x 6 inches
174,240
5 x 1 feet
8,712
15 x 15 feet
193
9 x 9 inches
77,440
5 x 2 feet
4,356
16 x 16 feet
170
1 x 1 foot
43,560
5 x 3 feet
2,904
16½ x 16½ feet
160
1½ x 1½ feet
19,360
5 x 4 feet
2,178
17 x 17 feet
150
2 x 1 feet
21,780
5 x 5 feet
1,742
18 x 18 feet
134
2 x 2 feet
10,890
5½ x 5½ feet
1,417
19 x 19 feet
120
2½ x 2½ feet
6,960
6 x 6 feet
1,210
20 x 20 feet
108
3 x 1 feet
14,620
6½ x 6½ feet
1,031
25 x 25 feet
69
3 x 2 feet
7,260
7 x 7 feet
881
30 x 30 feet
48
3 x 3 feet
4,840
8 x 8 feet
680
33 x 33 feet
40
3½ x 3½ feet
3,555
9 x 9 feet
537
40 x 40 feet
27
4 x 1 feet
10,890
10 x 10 feet
435
50 x 50 feet
17
4 x 2 feet
5,445
11 x 11 feet
360
60 x 60 feet
12
4 x 3 feet
3,630
12 x 12 feet
302
66 x 66 feet
10
33
Table 34. Times required to mow or trim lawn areas
In Minutes Per 1000 Square Feet - Or - Minutes Per Acre
(Numbers Rounded Up To The Nearest Minute)
Speed Is
And Width of Cut**Is
Miles Per
Hour
Feet Per
Minute
6"
12"
18"
24"
36"
48"
60"
72"
.25
22
91
46
31
23
16
12
10
8
.5
44
46
23
16
12
8
6
5
4
1.0
88
23
12
8
6
4
3
3
2
1.25
110
19
10
7
5
4
3
2
66
1.50
132
16
8
6
4
3
2
66
55
1.75
154
13
7
5
4
3
71
57
48
2.0
176
12
6
4
3
2
62
50
42
2.5
220
10
5
3
3
66
50
40
33
3.0
264
8
4
3
83
55
42
33
28
3.5
308
7
4
95
71
48
36
29
24
4.0
352
6
3
83
62
42
31
25
21
4.5
396
6
110
74
55
37
28
22
19
5.0
440
198
99
66
50
33
25
20
17
5.5
484
180
90
60
45
30
23
18
15
6.0
528
165
83
55
42
28
21
17
14
8.0
704
124
62
42
31
21
16
13
11
*Time=Min./1000 sq.
ft. above this Line
*Time=Min./Acre
below this Line
Some Average Speeds
**These figures are
for effective width of
cut, that is, width of
blade less operational
overlap averages = 4"
to 10"
Slow Walk - Pushing Mower . . . . . . . . . . . . . . . . . . . 150'/Min.
Slow Walk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 200'/Min.
Fast Pushing Mower .. . . . . . . . . . . . . . . . . . . . . . . . 250'/Min.
Modest Riding Yard Mower . . . . . . . . . . . . . . . . . . . . 275'/Min.
Fast Brisk Walk .. . . . . . . . . . . . . . . . . . . . . . . . . . . 300'/Min.
Good Riding Yard Mower . . . . . . . . . . . . . . . . . . 300'-350'/Min.
Tractor-Towed Riding Mower . . . . . . . . . . . . . . . . . 6-7 M.P.H.
1 Acre = 43,560 sq ft; 1 mile = 5,280 lin ft
34
Table 35. Cubic yards of soil needed at various depths and areas
Areas in 1,000 Sq. Ft. and Acres
½
1
2
3
4
5
6
7
8
9
10
½A
1A
2A
Depth in Inches
1
2
3
6
9
12
15
17
22
25
28
31
67
134
269
2
3
6
12
19
25
31
37
43
49
56
62
134
269
538
3
5
9
19
28
37
46
56
65
74
83
93
202
403
807
4
6
12
25
37
49
62
74
86
99
111
124
269
538
1076
5
8
15
31
46
62
77
93
108
124
139
154
336
672
1344
6
9
19
37
56
74
93
111
130
148
167
185
403
807
1613
7
11
22
43
65
86
108
130
151
173
194
216
471
941
1882
8
12
25
49
71
99
124
148
173
198
222
247
538
1076
2151
9
14
28
56
83
111
139
167
194
222
250
278
605
1210
2420
10
15
31
62
93
124
154
185
216
247
278
309
672
1344
2688
11
17
34
68
102
136
170
203
238
272
306
340
739
1479
2858
12
19
37
74
111
148
185
222
259
296
333
370
807
1613
3227
Table 36. Areas covered in square feet at various depths
Depth in Inches
Depth in Cu. Yds.
1
2
3
4
5
6
1
324
162
108
81
65
54
2
648
324
216
162
130
108
3
972
486
324
243
195
162
4
1296
648
432
324
260
216
5
1620
810
540
405
324
270
6
1944
972
648
486
390
324
7
2268
1134
756
567
455
378
8
2592
1296
864
648
520
432
35
Table 37 deals with temperature conversion.
Table 37. Temperature conversion
Fahrenheit ]
Centigrade (Celsius)
Centigrade (Celsius) ]
Fahrenheit
0
-17.8
-30
-22.0
5
-15.0
-25
-13.0
10
-12.2
-20
-4.0
15
-9.4
-15
5.0
20
-6.7
-10
14.0
25
-3.9
-5
23.0
30
-1.1
0
32.0
35
1.7
5
41.0
40
4.4
10
50.0
45
7.2
15
59.0
50
10.0
20
68.0
55
12.8
25
77.0
60
15.6
30
86.0
65
18.3
35
95.0
70
21.1
40
104.4
75
23.9
45
113.0
80
26.7
50
122.0
85
29.4
55
131.0
90
32.2
60
140.0
95
35.0
80
176.0
100
37.8
100
212.0
NOTES: 1) To convert temperature in degrees from Centigrade (Celsius) to temperature in degrees
Fahrenheit: Multiply Centigrade temperature by
1.8 and add
32. 2) To convert temperature in
degrees Fahrenheit to temperature in degrees Centigrade (Celsius): Subtract
32 and multiply by
0.55.
36
Formulas for calculating greenhouse volumes
These formulas are helpful in determining heating and cooling costs for greenhouses.
Figure 1-A. Formula for calculating uneven-span greenhouse volume.
L = length
W = width
1
W = width of short span
2
W = width of long span
e
H = height from floor to eave
r
H = height from eave to top
e
1
r
2
r
Greenhouse volume in cubic feet = [(H x W) + (W x H )/2 + (W x H )/2] x L
Figure 1-B. Formula for calculating even-span greenhouse volume.
L = length
W = width
e
H = height from floor to eave
r
H = height from eave to top
e
r
Greenhouse volume in cubic feet = [(H x W) + (W x H )/2] x L
Figure 1-C. Formula for calculating quonset greenhouse volume.
L = length
W = width
e
H = height form floor to eave
r
H = height from eave to top
37
Area of an arc segment = (A x R)/2
Area = 22.6 x 14.5)/2 = 164 ft2
But we do not need the area of the entire arc segment, only the area
actually present on the greenhouse; so we need to SUBTRACT OFF the
bottom triangles:
Area of a triangle = ½ (width x height) = a x b = 10 x 10.5 = 105 ft2
So the area of one gable end = 164 ft - 105 ft2 = 59 ft
2
2
Volume (above eaves) is area of gable multiplied by the length
of the greenhouse. Greenhouse volume in cubic feet =
e
(H x W x L) + (Volume above eaves).
Formula for calculating the surface area of the gable end, which is an arc segment.
A = arc length of the roof
R = radius of circle of which a is the arc
segment
�� = the angle forming the arc segment
R = c
r
c = b + H
a + b = c
2
2
2
tan
A = a/b
r
Examples: H = 4', W = 20'
R = c
C = b + 4'
a = 10'
(10) + b = (b + 4)
2
2
2
b = 10.5
c = 10.5 + 4 = 14.5' = R
A = (�� x R x ��)/180o
tan
A = 10/10.5
tan
A = 0.9524
arctan 0.9524 = 43.6o
�� = 2 x A = 2 x 43.6 = 87.2
o
o
A = (�� x R x ��)/180o
A = (3.14159 x 14.5 x 887.2)/180o
A = 22'6"
Formulas for calculating variously-shaped areas
These formulas are helpful in determining application rates for areas with specific shapes.
Knowledge of the areas is also helpful in estimating amounts of various soil amendments and
number of plants needed.
Figure 2-A. Square or rectangle
Area = Length x Width
Area = L x W
Area = (50') x (50')
Area = 2,5000 sq ft
Figure 2-B. Triangle
Area = ½ x Base x Height
Area = ½ x B x H
Area = ½ x (50') x (75')
Area = 1,875 sq ft
Figure 2-C. Circle
Area = �� x Radius x Radius
Area = �� x R = 22/7 (3.14)
2
Area = 3.14 x 20' x 20'
Area = 1,256 sq ft
38
Figure 2-D. Circle (within 5% accuracy)
Area = Diameter x Diameter x 0.8
Area = 0.8 x D2
Area = 0.8 x 40' x 40'
Area = 1,280 sq ft
Figure 2-E. Ovals or egg-shaped (within 5% accuracy)
Area = Length x Width at midpoint x 0.8
Area = 0.8 x LW
Area = 0.8 x 20' x 50'
Area = 800 sq ft
Figure 2-F. Irregular shapes (within 5% accuracy)
C Measure the longest axis of the area (length line).
C At every 10 feet on the length line, measure the width
at right angles to the length line.
C Total all widths and multiply by 10.
Area = (A + B + C + D + E + F) x 10
Area = (50' + 75' + 125' + 150' + 75' + 25') x 10
Area = 500 x 10
Area = 5,000 sq ft
Figure 2-G. Unusual-shaped areas
Calculation should be made for various sections.
In this case, calculate and add together:
Area of triangle
Area of rectangle
½ Area of circle
Total area = total sq ft of area
DISCLAIMER: Trade Named Products listed does not imply endorsement over similar products,
which may also be available.
39
Acknowledgments
The authors wish to acknowledge the following sources, certain tables from which were adapted to use in
this publication.
1 Ball RedBook, 16 ed. 1998. Vic Ball (Ed.) Ball Publishing.
1
Bedding Plants IV. 1994. J. Holcomb (Ed.) Ball Publishing.
1 Cornell Recommendations for Commercial Floricultural Crops, Part 1. Cultural Practices and Production
Programs.
1
Greenhouse Operation and Management, 5 ed. 1998. P. V. Nelson.
th
1
Hummert��s Helphul Hints, 1999-2000 ed. Hummert International.
1
Installation and Maintenance of Landscape Plants Bedding Plants. D.A. Bailey and M.A. Powell. 1999.
North Carolina State University A&T State University Cooperative Extension. Horticulture Information
Leaflet 555.
1
Light and fertilizer recommendations for production of acclimatized potted foliage plants. C.A. Conover
and R.T. Poole, 1984, Foliage Digest (vii) 6: 1-6.
1
Greenhouse Media Lab Acid Addition Calculator to Control Alkalinity in Irrigation Water .B.E. Whipker,
D.A. Bailey, P.V. Nelson, W.C. Fonteno, and P.A. Hammer. Cooperative Extension Services of the
Northeast States.
1
Nutrition of Greenhouse Crops, pH and EC Meters – Tools for Substrate Analysis. 2000. T.J. Cavins, J.L.
Gibson, B.E. Whipker, and W.C. Fonteno. North Carolina State University Research Report. Florex.001.
1
Tips on Growing Bedding Plants, 4 ed. 1999. O.F.A. Services Inc.
th
1
Tips on the Use of Chemical Growth Regulators on Floriculture Crops. 1992. O.F.A. Services Inc.
1
Tons to Teaspoons, L2285, University of California Cooperative Extension Service.
1
Water, Media and Nutrition. 1996. Alkalinity, pH and Acidification, Chapter 4. David Reed (Ed.) Ball
Publishing.
Bulletin 931
Reviewed April 2009
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