How to Add Phosphorus to an Organic Garden

Organic gardeners utilize organic soil amendments to improve the nutrient content of the soil. They don't use synthetic fertilizer at all. One of the natural fertilizers that you can use in an organic garden is phosphorus, so follow these steps to add it to your garden.

Difficulty: Easy

Instructions

Things You'll Need:

• Compost
• Bone meal
• Rock phosphate

1. Maintain a compost pile. Food wastes contain high levels of phosphorus, and are free. In addition, compost supplies many other nutrients that will keep your plants happy and healthy.

2. Find bone products at a garden supply store to supply your garden with phosphorus. You can get bone meal, acidulated bone or ground bone, depending on your needs. Bone meal can contain anywhere from 20 to 30 percent phosphorus, depending on whether the bones were steamed or not.

3. Apply bone sources of phosphorus as directed on the package. Directions will differ among the different types, because of the amount of phosphorus they contain.

4. Consider using rock phosphate for your organic garden's phosphorus needs, especially if you are vegan or don't want to use animal products in your garden. As its name suggests, rock phosphate is made from rocks. Remember that rock phosphate is most effective acidic soils, but less effective in alkaline soils. In addition, rock phosphate is a good addition to compost.

5. Add about 2 to 4 lbs. of rock phosphate to your garden for every 100 square feet of ground, depending on the severity of the phosphorus deficiency. If you choose to add rock phosphate to your compost pile instead, add 2 ½ lbs. to every 25 lbs. of compost.