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When to Fertilize & Apply Weed Killer to a Lawn?

Everyone knows that a beautiful, manicured lawn adds to the value of a property as well as the neighborhood. Maintaining a lawn requires some knowledge of when to fertilize and apply weed killer, though. The time of year and where you live will determine when you should use fertilizer and weed killer. When you take those factors into consideration and follow a few simple guidelines, maintaining a healthy, verdant lawn should be fairly easy.

Before Fertilizing

Before you purchase anything, it is important to identify the type of grass you have on in lawn. A large proportion of the United States has transitional grass, which means that warm and cool season grasses can grow in the region. In the southern region of the country, warm season grasses will turn brown after the first frost. In the northern region of the country, cool season grasses will generally stay green all year long.

Next, conduct a soil test. This is important because the pH balance of your soil will determine if the fertilizer and weed killer can be used correctly. A pH balance of 6.0 or 7.0 is ideal for growing the best grass. Determine the size of your lawn by multiplying the width of your lawn by its length. Subtract the square footage of the house, driveway and other areas not to be fertilized. According to the instructions on the bag of fertilizer, you should now know how much to purchase to cover your entire lawn.

Cool-Season Grasses

Ideally, fall is the best time to fertilize and apply weed killer to your lawn. Cool season grasses respond well to fertilizer and weed killer between August and November. During this time of dormancy, it’s important to lay the groundwork for the root system and strengthen the soil for a healthy lawn in spring. During the spring, fertilizer and weed killer should be applied, again, but with a slightly lighter application. The goal is to encourage growth and feed the roots without overfertilizing, so that the roots are weakened. If by chance you overfertilize during the spring, you can expect weeds during the summer. Should a second application of fertilizer be needed, during the fall or spring, it’s best to wait for 4 weeks after the first application.

Warm-Season Grasses

Since warm season grasses are dormant during winter and turn brown, May is considered the best time to start fertilizing and applying weed killer. Because the grass will be growing simultaneously as you fertilize it, once a month is recommended, until September. But, if you fertilize after September 1 in some areas, you could delay the dormancy period of the grass. Fall is a good time to use a winterizer formula on your lawn to build strong roots to protect the lawn during the winter. In addition, in February, you should use a good pre-emergence herbicide to tackle any weeds. This will ensure that weeds won’t have a chance to germinate before spring arrives.

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