Rain Washes Away Fertilizer Into Local Waters: Myth Debunked


By Rick Orr
Pest Control Tech spraying a St AUgustine lawn by Tampa Bay
Lawns don't Pollute - They De-Pollute by filtering out pollution including fertilizer and lawn chemicals

It is Science

The science behind why the rain does not wash away the fertilizer is basic organic chemistry - chemical bonds between charged particles. It is like a magnet and iron filings - organic matter (grass leaves, debris, and the soil microbes) are the magnets and the fertilizer spray is the iron fillings. When we spray your lawn the fertilizer is tightly held onto the organic matter by chemical bonds. These chemical bonds cannot be broken by rain, so the rain cannot wash away the fertilizer or chemicals.

Water In after Application

Rain or irrigation after application helps our fertilizer and chemicals to stay on the lawn. The instructions printed on the label require that our spray be watered in after being applied to the lawn. This helps spread the fertilizer over more surfaces. The more surfaces, the more the chemical bonds, the more chemical bonds the more tightly the fertilizer and chemicals are held in the lawn.

Rain Does Not Wash Away the Fertilizer

Did you ever notice how lawns turn green after the rains? If the fertilizer washed away with the rains, the lawn would turn yellow, but it doesn’t. Why? Because the rain did not wash away the fertilizer! 

Moist Soil Is Critical to Survival 

A dry soil starves a plant – wet soil feeds a plant. A plant must have moist soil to absorb the nutrients clinging to the organic matter. When a lawn is well watered – like after a rain - it can absorb more nutrients, be healthy, and thrive. Whereas a dry lawn is yellow weak and often in a “survival mode” of just barely living. To take full advantage of lawn spraying you should be generous with the water.

A Tall Canopy Helps

Mowing at 4” or higher increases the amount of surface area in the lawn. The more surface area, the more chemical bonds. To take full advantage of lawn spraying you should mow your lawn at 4” or higher.

Rick Orr Owner-Staff Agronomist Barefoot Grassl/Creator of ILOVETURF.COM
Staff Agronomist at Barefoot Grass

Since 1995, Rick Orr has worked in Pinellas County providing turf management and pest control. Rick Orr is a graduate of VA Tech in Agronomy (Turf Ecology) and the creator of Iloveturf.com. 

Since graduating from VA Tech in 1979, Rick worked in the green industry, mostly with golf courses, resorts, and large communities. Rick has obtained certifications in arboriculture, landscape, irrigation, and taught Environmental Horticulture at St Petersburg College. 

Currently, Rick is the Staff Agronomist at Barefoot Grass in Largo, FL. To learn more about Barefoot Grass https://www.barefootgrass.com/ Free Price Quote from Barefoot Grass for Home Pest Control and/or Lawn Care https://www.barefootgrass.com/contact-weed-control/ 

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