Agriculture Reference
In-Depth Information
Potassium sulfate.
Also called potash of sulfate, potassium sulfate is a valu-
able fertilizer in conventional farming systems. Unfortunately, it is usually
produced in factories and naturally occurring forms that can be mined are
evaporating saline lake water. Not all sources of potassium sulfate are suit-
able for organic production and not all certifying organizations allow its use.
Sul-po-mag is a good alternative product. If you use potassium sulfate, en-
sure that it is allowed under your certification guidelines.
Shells.
Ground oyster, clam, lobster, and crab shells are similar to bonemeal
in some ways. They are rich in calcium but rather low in phosphorus. A typic-
al crab shell-based fertilizer might contain 2 to 3 percent nitrogen, 3 percent
P O , 0.5 percent K O, and 23 percent calcium. Nutrients from shell products
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become available slowly. Shell products are probably best used as slow-re-
lease forms of calcium.
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Sodiumnitrate.
Also known as Chilean nitrate, this is a nitrogen-rich, rapidly
available fertilizer. Because of its high sodium content, most organic certific-
ation programs discourage or prohibit its use. Some certification programs
allow Chilean nitrate to be used, but only enough to provide 20 percent of the
total amount of nitrogen applied. This material is best used sparingly during
the early stages of establishing an orchard or as an occasional supplement
when a quick fix of nitrogen is needed. Ensure your organic certification or-
ganization allows its use before applying it to your crops.
Sugar beet lime.
In processing sugar beets, limestone is heated to produce
calcium oxide and carbon dioxide, which are then mixed with the beet juice
to absorb impurities. During the process, the calcium oxide and carbon diox-
ide recombine to form calcium carbonate, which must be disposed of. Sugar
beet lime can be useful as a soil amendment to raise pH, but the material
often contains large amounts of water, making it difficult and expensive to
