Trisodium Phosphate & Gardening

Trisodium phosphate, more commonly referred to as TSP, is often used as a household cleaner. But TSP has many uses, including eliminating potential diseases in vegetable plants and as a pesticide for various crops. Because of its wide use, trisodium phosphate is easily available, inexpensive and very effective for disinfecting tools and killing harmful fungus and bacteria throughout your garden and home.

Trisodium phosphate, or TSP, is a chemical compound that will clean, disinfect, degrease and remove stains. It can be purchased in powdery, granular form and easily dissolves in water. Often found as an ingredient in soaps and detergents because of its unmatched cleaning ability, trisodium phosphate was found to have a harmful impact on the environment. This is due to the fact that TSP has a high pH, or alkaline value, and when introduced in large quantities to lakes, pond and other waterways, it increases the levels of algae growth. Today, trisodium phosphate is still available for household use, but in industrial applications more environmentally friendly substitutes are utilized.

Using a heated water and trisodium phosphate solution to disinfect seeds is particularly successful for tomato and pepper seeds that may have been exposed to tobacco mosaic virus. Placing the vegetable seeds in a cotton bag and soaking them for 40 minutes in a solution of 1 lb. trisodium phosphate with 1 gallon of water heated to 122 degrees Fahrenheit will decrease the transmission of the virus. After the 40-minute soak, rinse the seeds, air dry them and treat them with a protective fungicide before planting.

One of the best applications for trisodium phosphate in your garden is to use it to clean and sterilize tools, especially if you have been using the tools to remove part or all of a diseased plant. After thoroughly washing your tools -- including pruners, shovels and trowels -- with warm soapy water, soak the tools for 30 minutes in a solution of TSP and water. The mixture needs to contain a concentration of trisodium phosphate that is recommended for washing clothes or dishes with a detergent. Do not rinse the trisodium phosphate and water mixture off your garden tools after soaking, but allow them to air dry.

In large tree crops, trisodium phosphate is sprayed to kill fungal diseases and mold, thereby eliminating the foods harmful insects and pests feed on. Trisodium phosphate is toxic and creates a burning sensation when breathed, ingested or comes into contact with sensitive skin. It is not recommended for home gardeners to use trisodium phosphate as a pesticide or fungicide spray application. Only a professional with experience in mixing and applying this chemical is qualified.