Phosphorus is essential for strong root growth, for the production of flower and seeds and for greater resistance to diseases. It is also necessary to the production of plant sugars and is the mechanism by which sugars move within the plant. Symptoms of phosphorus deficiency are: slow growth, dwarfing, purplish leaves, stems and branches, poor flower productions. Excessive phosphorus can cause problems, especially in bodies of water where it is introduced, usually through runoff. Among these are eutrophication (an increase in chemical fertilizer which causes excessive growth, depleting oxygen and reducing populations)and algal blooms (an increase in algae growth). Although, the percent of P to N is needed in smaller quantities, it is vitally important to good root growth. It will affect the plant growth if there is a deficiency. Phosphorus can become locked up in the soil and is the most difficult to be released. Most plants cannot extract nutrients from unbalanced soils. If the pH is to high or to low, phosphorus becomes unavailable. This is called phosphorus fixation and is especially prevalent in acid soils.

Phosphorus does not travel far through the soil. If the soil is dense or compact the roots can not travel to the areas or pockets of phosphorus. Helping your soil to become less dense will allow air, nutrients and moisture in the garden. With improved soil structure the roots can access the pockets or areas of phosphorous by growing to them. Much of the nutrients in the soil are the result of decaying organic matter. Working vermicompost into a new bed will provide much of the nutrients for the beginning season. Vermicompost, besides containing nutrients, also has microbes and biomass which is so important in building up your soil. 

To help break down phosphate rock to a usable form for plants there are limited bacteria and fungi that can accomplish this process. The larger the number of these organisms along with proper conditions in the soil, allows the best production of soluble phosphate. In several scientific studies, it was found that these bacteria (which seem to be the most effective in breaking down phosphate) increased quicker and with higher concentration when compost was added to the mix.

Phosphorus has been tested and shown effective in treating and inhibiting plant diseases, such as downy mildew. Foliar feeding can be used to enhance the buildup of nutritious value in plants so spraying directly on leaves can increase not only the phosphorus content, but may increase the ability of the plant to resist disease. Many products which include ingredients from the sea include quantities of phosphorus. Phosphorus is part of the runoff and settles on the ocean floor. It is then taken up by plants and sea life in the ocean and in turn harvested and processed into fertilizers. 

The ideal process for including organic phosphorus in your soil would be as you prepare the bed. Incorporating vermicompost along with the phosphorus will invigorate the planting medium and give your plants the best choice. If you are adding plants to an existing bed, add some organic vermicompost in the bottom of the hole along with a supply of whatever type of phosphorus you wish. There will need to be a continuing of renewal by applying organic fertilizers and allowing them to be worked into a quality soil that will continue to be improved by additions of virmicompost promoting increased microbial activity in the soil.