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Ahead, read our guide to understanding weed-and-feed products, as well as the details on our top-favorite picks among the best weed-and-feed options available.

The right weed-and-product can improve the health and appearance of your lawn. Ahead, get our top tips and recommendations for navigating the available options—and don’t miss our top picks!

Weed preventers, or preemergent weed killers, block weed seeds that are already in the soil, like crabgrass, poa annua, chickweed, and henbit, from germinating. Identify the type of weeds that are infesting your lawn and then make sure you choose a product that’s made to take care of it.

Selecting a fertilizer and weed killer that’s compatible with your grass species will give you far better results. Different nutrients have different effects on your lawn, from enhancing color to developing stronger root systems. Additionally, since many products include herbicides or weed preventatives, it’s important to know the types of weeds that come up in your lawn.

There are at least 11 states that ban phosphorus fertilizer use or sale. Luckily, many lawn weed and feed products available have adapted to this and have removed phosphorus from the product. Don’t worry—the weed and feed will still green up and thicken the grass without the additional phosphorus.

Avoid the need for weed preventers by keeping your lawn healthy. Once established, only water your turf once a week during the growing season. Up to 1 inch of water during this watering session allows roots to search deeply for moisture to create strong grass. Shallow grass roots die in stressful conditions, like drought, and allow weeds to grow in thinned spots. Allow your turf to grow to a healthy height as well, typically between 1 and 3 inches, depending on the species. Long grass blades mean the grass can produce enough energy to stay healthy and compete with weeds. In short, healthy and well-maintained grass has less problems with weed growth.

Cool-season grasses are usually seeded, as opposed to warm-season grasses that usually need to be grown from sod or plugs. Because cool-season grass seeds germinate best in fall, apply your chemical preventer in spring to actively kill off weeds in spring and summer. In general, temperatures between 65 and 70 degrees Fahrenheit are good for weed preventer application. Hot days often cause the chemicals to vaporize into the atmosphere, reducing their effectiveness. By the time fall seeding weather arrives, the chemicals are no longer active and the grass seeds will be able to sprout.

Chemical weed preventers, also called preemergent herbicides, are usually granules or liquids, but both require water to work. As the preventer soaks into the ground, it leaves a residual film in the top 1-inch of soil. Because most seeds germinate at or just below the soil’s surface, these preemergent herbicides remain active against any germination processes for up to four months, depending on the chemicals involved. Organic weed preventers work in a similar way. With many weeds being members of the grass family, all seeds, including desired lawn species, fail to germinate and sprout after you’ve used a weed preventer.

Seed Correctly

Even if you time your weed preventer and seeding periods correctly, you need to do the job right to get an even lawn with no bare patches. Apply seeds uniformly across your yard using a drop spreader on a mild fall day. Spread up to 1-inch of organic mulch over the seeds to conserve moisture and encourage germination. Water the seeds at least twice a day for short, 10-minute sessions. You do not want to wash away the seeds, but they need consistent moisture to grow. Hand pull any weeds that appear while the grass seedlings develop. Do not apply any chemicals for weed control.

Spreading seed is an inexpensive way to grow a lush lawn, but exposed soil between germination and establishment makes it vulnerable to weeds. Although chemical weed preventers have different mixtures and instructions, you should not apply them while seeding or immediately afterward. You must allow one to four months between applying this type of chemical and spreading seed.

Writing professionally since 2010, Amy Rodriguez cultivates successful cacti, succulents, bulbs, carnivorous plants and orchids at home. With an electronics degree and more than 10 years of experience, she applies her love of gadgets to the gardening world as she continues her education through college classes and gardening activities.

The weed seeds are prevented from reaching the soil, and thus, they can’t proceed with their germination.

Rake your lawn so you can remove dead grass and roots. Preemergent’s should take care of any weeds before they take hold. You need to apply this in the spring before the temperature reaches the range of fifty Fahrenheit and above.

How to Add a Pre-emergent Weed Killer

One of the primary ingredients in Roundup is glyphosate, which in its own right, is one of the most widely used herbicides in near enough every country.

Getting any of these wrong can ruin your lawn, or you can find you sow your lawn, and the seeds don’t grow because of weed killer traces.

The issue with Roundup is it is a non-selective herbicide, meaning gardeners do need to take care of where they spray it.