Speaking of soil testing time, one result that we often find in soil tests that come back from the lab is bound-up, high levels of Phosphorus. This mineral is very hard to unlock, so this work is undertaken over several seasons. The ideal level of Phosphorus is 75 ppm (parts per million). We often find levels in the 400-500 ppm range!  Or higher!  Insects gravitate to plants with high levels of Phosphorus since their simple digestive systems find them quite attractive. As you reduce Phosphorus, you’ll also reduce insect predation.

Phosphorus is essential for bloom, seed set, and root growth. It helps convert other nutrients into usable building blocks for growth. Excessive Phosphorus does not help plants and can pollute nearby natural water sources.

The first thing to do is not to add any more Phosphorus. That means zipping up the bag of Bone Meal, Rock Phosphate, or Superphosphate (this last is a synthetic fertilizer and isn’t allowed in an organic program, anyways, per NOFA Organic Land Care Standards).

Instead, we will look at the levels of other minerals in your soil, such as Magnesium, Sulfur, Calcium, and Potassium. Some of these (or all) may be on the low side. So we will look to boost them. Retesting the next year usually shows a reduced level of Phorphorus, meaning that (at last) it has been released to your soil.

 

 

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