Weed infestations and infertile soils are common problems for home lawns. These problems usually go hand-in-hand because lawns do poorly in unfertilized soil, and that leaves room for weeds to move in. Many companies make a product which both kills weeds and fertilizes your lawn at the same time. The weed killer and fertilizer, typically known as "weed and feed," can be applied at the same time and saves time and money compared to applying two separate products.
Mow your lawn to its regular height one to two days before you plan on applying the weed and feed.
Set up lawn sprinklers and irrigate your lawn the day before you want to apply the weed and feed. Irrigate to provide 1 inch of water over the entire yard.
Apply the weed and feed in the morning when there is still dew on the grass. Fill your broadcast spreader with the product. Set the dial on the broadcast spreader to the indicated setting on the weed and feed bag. Push the spreader over your entire yard to apply the product. Walk in the same fashion as you would when mowing your grass.
Water your lawn two to three days after application in the same manner as you did in step 2.