Michigan State University Extension
Soils & Soil Management - Fertilizer - 06209711
07/10/97
Fluid Fertilizers--Liquids and Suspensions MSU Ag Facts Extension Bulletin E-933, December 1984, Revised, destroy previous editions
by R. E. Lucas and M. L. Vitosh, Department of Crop and Soil Sciences
Fluid fertilizers are often used to make starter solutions for transplants. Fertilizers in solution are readily taken up by the plants. This promotes new growth and better plant survival. Many all-soluble dry fertilizers also can be used in starter solutions. To prevent salting out, use soft or low-lime water. Rain water or distilled water is best for making a concentrated starter solution from dry fertilizer.
The maximum amount of fertilizer in a starter solution will depend upon the carriers. Follow the manufacturer's recommendations. Normally, 5 to 8 pounds of an all-soluble dry fertilizer are added to 100 gallons of water. Concentrated liquid fertilizers such as 10-34-0, 10-20-10 etc., are diluted 100 to 150 times by volume. The starter solution is then applied directly to the transplant at the rate of one-half pint per plant.
In preparing liquid fertilizers from dry fertilizer, you may need to dissolve the fertilizers in hot water. The solubility of various fertilizers. varies greatly. (See Table 2 for approximate solubilities for some common fertilizers.)
==================================================== Table 2: Approximate solubilities of some common fertilizers.
Parts Soluble in Fertilizer
100 Parts of Cold Water
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ammonium nitrate 118
manganese sulfate 105
calcium nitrate 102
urea 78
zinc sulfate 75
sodium nitrate 73
ammonium sulfate 71
magnesium sulfate 71
calcium chloride 60
diammonium phosphate 43
potassium chloride 34
monoammonium phosphate 23
potassium nitrate 13
superphosphate (0-46-0) 4
borax 1
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