Editor’s Note: Although fertilizers are a garden or yard-improvement option, they are also a major source of water pollution. The nutrients in fertilizers, such as nitrogen and phosprous, are bad for humans and the environment when they leach into surface water and underground drinking water. Excess nutrients in the soil can also harm crop production. Compost and other environmentally-friendly soil-improvement techniques can be used in place of fertilizer. For more information, click here to visit the EPA’s website for “Greenscaping.”

You can apply dry lawn fertilizers with either drop spreaders, which apply the fertilizer to a narrow band of grass directly below the spreader, or broadcast spreaders — handheld or wheeled — which throw fertilizer over a wider area and are particularly useful for large lawns. (If you don’t need this equipment often, both are available at rental yards, and many nurseries loan them.)

Applying dry fertilizers evenly by hand is very difficult. If you have no other option, apply the fertilizer very carefully and only on small lawns. Wear gloves and walk backwards across the lawn as you throw the fertilizer as evenly as possible with a sweeping motion. You can apply liquid or water-soluble fertilizers with handheld, hose-end applicators. Liquids are more difficult than dry fertilizers to apply evenly and the handheld sprayers require frequent refilling on large lawns. When using liquid fertilizers and handheld sprayers, follow the label instructions precisely.

The key to applying fertilizer evenly is to properly use the spreader. Uneven fertilizer application leads to uneven greening or burning of the grass. Take the following steps to achieve a well-nourished, attractive lawn:

1. Set the spreader settings to correspond to the amount of fertilizer you want to apply.
   The information you need is on the fertilizer label or spreader instructions. If not, you need to calibrate the spreader.
2. Place the spreader over a hard surface (such as a driveway or walkway) and fill it with fertilizer.
   Sweep up any fertilizer that spills.
3. Start at the edges of the lawn first, as shown in the image below.
   Move at your normal walking speed. Then move back and forth between the edges. To avoid missing strips when using a drop spreader, make sure to overlap the path of the wheels. Turn the spreader off when you reach the end strips, when you come to a stop, or when you’re turning around to avoid uneven application.

   

4. Water the lawn thoroughly after fertilizing.
   Fertilizer can burn your lawn if it remains on the leaves. To avoid this, water in the fertilizer to wash the nutrients into the soil where lawn roots can use them and where heavy rains won’t wash them away. When you finish, clean the empty spreader with a hose to avoid corrosion. Wash out the spreader on the lawn and let it dry before storing.  ....read more