Maintaining a healthy lawn is good for the environment, so we often turn to seasonal lawn fertilizers to feed our lawns and cultivate that rich, green carpet of grass.
However, many lawn fertilizer products contain phosphorus, which can result in pollution to waterways and watersheds if not used properly.
Since phosphorus from grass or lawn fertilizers is absorbed slowly into soil, and plants use only small amounts, excess phosphorus runoff can cause algae to build up in waterways, disrupting the ecological balance. Some states and townships have even legislated or promoted against the general use of phosphates in lawn fertilizer.
Using phosphorus-free lawn fertilizer is one easy way anyone can contribute to a healthier environment, regardless of where you live.
Tip: When shopping for lawn fertilizer, look for the three numbers on the lawn fertilizer bag. The middle number indicates the phosphorus content of the fertilizer, so look for a 0.
The other numbers indicate the amount of nitrogen (first number) and potassium (third number) in the fertilizer.
For example, if the lawn fertilizer has a string of numbers like 12-0-24, this means the fertilizer contains 12% nitrogen, zero percent phosphate and 24% potassium.
Phosphorus in a lawn fertilizer is typically needed only on newly seeded lawns or where soil testing indicates a deficiency.
Here are some more tips for spreading lawn fertilizer:
- Avoid applying lawn fertilizer when heavy rain or thunderstorms are forecast, or if the soil is already saturated.
- Apply lawn fertilizer when the soil is dry or moist, then water it in lightly.
- Use a drop spreader rather than a spinner to avoid spraying lawn fertilizer onto impervious surfaces such as sidewalks and road gutters.
- Avoid mowing in a way that grass clippings are blown onto impervious surfaces. Clippings contain phosphorus and contribute to potential runoff.
