At the recent GreenTrends conference held by Florida Green Building Coalition (FGBC) I spoke with several of the vendors, including a representative from Think About Personal Pollution (TAPP), a campaign that helps educate people on ways that small personal changes in home and yard practices can help keep local lakes, sinks and streams cleaner. Even though the website was developed to educate residents of the Tallahassee area, the information pertains to everyone. I especially like their slogan “Every drop you lose, nature finds. Slow the Flow.”
One of the articles from the TAPP website discusses lawn fertilizers. I learned fertilizers without phosphorus would make for greener lawns, healthier plants and lakes. Why…
Most fertilizers contain nitrogen, phosphorus and potassium, reported to us by those familiar numbers on the bag (8-8-8, 16-4-8, etc.). Nitrogen, the first number, is an essential component of chlorophyll (which makes plants green) and helps supply plants with energy to grow. Phosphorus,the second number, promotes flowering and seed production – but how many of us want to encourage our lawn to flower and seed? It does not make grass green. Potassium, the third number, strengthens the plant against times of trouble such as drought, frost and disease. Because most Florida soils are already rich in phosphorus, local soils most likely need 15-0-15 for healthy, green lawns.
Most homeowners aren’t aware that lawns in this area don’t need a dose of phosphorus – they already have enough. Generally, local soils have all the phosphorus that plants need, and for yards bordering a lake, phosphorus can be harmful. When phosphorus is applied to the yard and not used by the grass, it runs off into the lake where it feeds algae and invasive plants, stimulating flowering and seed production. According to Craig Diamond with the Tallahassee-Leon County Planning Department, a 1993 survey showed, “there were over 1000 applications of fertilizer in the (Lake Jackson) watershed (per year), averaging nearly 22 TONS total weight”. Diamond says that these fertilizers contribute one half to one ton of phosphorus each year to Lake Jackson. Jess Van Dyke, lakes biologist with Florida Department of Environmental Protection, reports that taxpayers spend $8 per pound to remove phosphorus from sediment in Lake Jackson. As he says, “it is a lot less expensive to apply phosphorus that it is to remove it.”
Source: TAPP – Think about Personal Pollution