seeding over weeds

If you are faced with a neglected lawn that’s partially dead and is being taken over by weeds, you may be able to renovate it. Restoring a deteriorated lawn may be possible if the weeds and dead spots cover less than 40 percent of the lawn area. Renovation of a weedy lawn involves more than just mowing down the weeds and throwing some grass seed over the lawn.

If you have had a dry summer with below-normal rainfall, you need to replenish soil moisture before preparing a seedbed. Give the entire lawn a thorough watering, soaking until water has penetrated to a depth of at least 6 inches, then allow the surface to dry for a day or two before starting soil preparation.

The best time for lawn renovation throughout the U.S. is mid-August to mid-September. Most weeds have not yet dropped their seeds and there will be little new weed growth. Also, reseeding at this time will give the new grass a chance to establish itself before going dormant for winter. Get rid of the weeds by manually pulling up large, spreading weeds. Follow up by applying a selective herbicide product that kills common broadleaf lawn weeds while not harming grass. For tough grassy weeds, like quack grass or crabgrass, use a nonselective herbicide such as glyphosate on the spots where these weeds have established themselves. Normally, all weeds will be dead within two weeks. Apply another herbicide dose in three weeks to get newly sprouted weeds.

Kill the Weeds.

The soil nutrients most important to healthy grass plants are nitrogen, potassium and phosphorous. Supply these nutrients by applying a commercial fertilizer formulated for starting lawns and lightly rake it into the soil before you reseed. Buy a grass-seed blend suited to your climate and local conditions and spread it over the lawn with a drop spreader or rotary spreader. Absent a different recommendation from the grass-seed grower, spread the seed at a rate of 2 pounds per 1,000 square feet on a lawn with substantial plots of live grass and 3 pounds per 1,000 square feet on bare soil. Water lightly once or twice a day to keep soil moist but not sopping wet. Don’t mow until the new grass gets 3.5 inches tall.

Most deteriorated lawns have a built-up layer of dead and partially rotted grass stems, roots and rhizomes just below the green grass leaves. This is known as thatch, and it must be removed before reseeding so water and fertilizer can reach the new seed. For small lawns, you can remove thatch with a garden rake. For large areas, go over the lawn with a power dethatcher, also known as a vertical mower or power rake. These machines can be rented from garden centers. Remove the clumps of matter left by the machine with a garden rake and level the soil by raking it.

Herb Kirchhoff has more than three decades of hands-on experience as an avid garden hobbyist and home handyman. Since retiring from the news business in 2008, Kirchhoff takes care of a 12-acre rural Michigan lakefront property and applies his experience to his vegetable and flower gardens and home repair and renovation projects.

Water the Site.

Remove Thatch.

There are 13 references cited in this article, which can be found at the bottom of the page.

This article was co-authored by Lauren Kurtz. Lauren Kurtz is a Naturalist and Horticultural Specialist. Lauren has worked for Aurora, Colorado managing the Water-Wise Garden at Aurora Municipal Center for the Water Conservation Department. She earned a BA in Environmental and Sustainability Studies from Western Michigan University in 2014.

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A patchy and weedy lawn is unpleasant and unappealing. Luckily, there are ways you can get rid of the weeds and replant grass seed to have a lush lawn. Before you start, it’s important that you purchase the right type of seed for your environment and you test your lawn so you know which kind of amendments and compost to use. If your lawn is really spotty and full of weeds, you should kill all of the weeds and old grass in your lawn and start over. If you only have a few weeds, you can spot weed and reseed.

Aside from choosing the best time, you must prepare your lawn for overseeding to work the best.

You’ll probably want to review my guide to watering new grass to improve your results.

The most important things with overseeding are preparation and timing.

Overseeding at the right time of year, before weeds are established or after annual weed pressure begins to ease, will ensure success.

If you want to give your lawn a hard reset, late autumn is the better choice as your new grass will not have any pressure from annual weeds.

Preparing Your Lawn for Success.

After 2 weeks, water heavily and less frequently. You want the soil saturated down to 6-inches each time you water it past the 2 week point. This will encourage your grass seedlings to grow deep roots which will improve your lawn’s resilience to heat and drought.

If your lawn is thin, and you want it to grow in thicker to prevent weeds from growing, early spring is your better bet.

Overseeding is the method of revitalizing a yard by adding more seed into an existing lawn.

Similarly avoid herbicides for several weeks on new grass.

The hot summer months are very harsh for new grass seedlings, so springtime isn’t quite as good for most weedy lawns.

You can’t overseed a weedy lawn in the summer when all of your weeds are mature and growing vigorously. You’ll be wasting your time and money if you try that.

The time of year when you overseed your weedy lawn will depend upon why you’re doing it in the first place.

Before you begin spreading seed, check the label on the grass seed you purchase for the rate of overseeding. Most bags of grass seed will provide this information right on the bag.

The best way to get rid of weeds, oddly enough, is to grow a lawn lush enough to kick them out.

Seeding your Lawn.

Spreading a thin (1/4 inch) layer of compost over the new seed will work wonders to improve germination and help your new seedlings thrive.

I like to spread some quick-release starter fertilizer on the lawn before spreading my seed. Scott’s makes a really good product (Amazon link), and it’s particularly good for Spring overseeding because it has a crabgrass preventer in the mix.

Wait several weeks before mowing your lawn.

You want to get the right amount of seed in your yard—too much will keep grass from growing because the seedlings compete for moisture, too little and your yard will stay thin and ripe for weed growth.

You don’t have to till your lawn, and you don’t have to tear it up for over-seeding a lawn to be effective.

It’ll take a good amount of work, but the results are worth the effort if done correctly.

How Overseeding Can Help Your Lawn.

If weeds don’t have a place to grow, they’ll stay out of your yard.

If you used starter fertilizer, I recommend throwing down organic slow-release fertilizer after 4-6 weeks to sustain and feed your new lawn and keep it healthy.

Anyone who’s had to care for a lawn of their own knows how easily weeds can spread. Once they get into your yard, it’s almost impossible to get them out, no matter the number of herbicides you use. That’s because weeds are opportunistic and will claim any bare or thin patch they can find in your yard. But is overseeding weedy lawn areas a good option? Or will the weeds just crowd out your new grass. I’ll discuss in today’s article.

Let’s talk about effectively overseeding weedy lawn areas and the best times of year to do so.

When you do mow, bag your grass clippings the first few times, and adjust your mowing deck to cut no more than 1/3 of the grass blade.

Once these steps are done, it’s time to spread seed onto your yard.

New grass needs a lot of water, and you want your soil to stay constantly moist.