One way homeowners can improve the look and health of their grass is by overseeding a weedy lawn. Learn the overseed definition, benefits and the step-by-step process of how to overseed. In this post, you’ll get answers to common questions, including FS584, The secret to a thick full lawn is overseeding.
Overseeding Weedy Lawn: Homeowners Take Back Their Yards
When you look out over your yard, does the sight you see bring you a sense of pleasure and pride, or do you cringe with embarrassment? If you’re in the latter camp due to unsightly weeds and patchy, lifeless grass, don’t despair—and don’t give up! Your yard doesn’t have to be the neighborhood eyesore, and you don’t have to declare your neglected lawn a total loss.
Depending on the severity of your situation, it’s possible that you’ll need to re-sod the entire area, but a far easier fix might work just as well. The simple yet highly effective key lies in overseeding weedy lawns to reclaim the lush, green, beautiful grass that all homeowners desire.
Let’s find out how just a bit of time, care and know-how will help you resuscitate your ailing lawn into a thing of emerald, weed-free beauty.
Overseed: Definition And Benefits
The term “overseed” may sound technical and even intimidating if you aren’t familiar with the process, but it’s really a simple gardening concept: Overseeding is simply the process of planting new grass seed over your existing grass in order to create a revived, newly green and beautiful lawn that is lush and healthy.
When you overseed your lawn, you build on its current strengths while working hand in hand with nature against its weaknesses. With a bit of elbow grease, the result is a lush, weed-free lawn that your neighbors will envy.
But how do you know if your yard is a good candidate for overseeding? Grass that is looking tired, patchy or weedy is prime for this relatively easy option for homeowners who want to help their yards recover. If weedy patches and bare spots make up less than half your lawn, overseeding is an excellent option for you. It is certainly easier and more cost-effective than digging up your entire yard and laying down all new sod, which can be an expensive and painstaking process.
Our Answer To The Common Question: When To Overseed My Lawn?
Many homeowners ask themselves, when is the best time of year to overseed my lawn? No matter which region of the country you call home, there are two times of year that are best for overseeding: early spring and late summer (mid-August to mid-September).
The spring option is best for homeowners who use non-organic fertilizer products containing chemicals that would stop new grass seeds from growing. By overseeding in early spring, you’ll give your existing grass and soil the most time possible to shed all the chemicals that could impede fresh growth.
If non-organic fertilizer use isn’t an issue for your yard, you might opt to overseed in late summer instead. This is generally the time of year when weeds grow the least, making it the best time to address weeds aggressively and effectively. This is also a great time of year to facilitate new grass growth before your turf goes dormant for the winter.
Why Do I Have Weeds In My Lawn In The First Place?
Before we get into the step-by-step process to overseed your lawn, it’s important to discuss how your grass got so weedy and patchy in the first place. After all, you don’t want to put in a lot of work just to have the same issues develop again in the future. So why do you have weeds in your lawn? How do these pesky, fast-growing plants move in and take over?
There are many factors that can contribute to a weedy lawn, including watering too much or too little, setting your mower blade too low, not mowing often enough or having a yard with poor drainage. Essentially, weeds are opportunistic; they grow when and where they can. Grass that is less than thriving provides the necessary space and opportunity for weeds to move in.
When weeds do begin to pop up here and there, chemical weed killers might appeal in the moment, but these products can actually be dangerous for people and animals, not to mention for your grass itself. Plus, if you aren’t careful, you’re likely to find yourself relying more and more often on weed killers to spot-treat your problem instead of resolving it at its source: by growing grass that is dense and vigorous.
The simple truth is that a thick, thriving lawn is the best weed deterrent on the market. Savvy homeowners know that keeping weeds away for good isn’t about finding the right herbicide product—it’s about keeping your grass dense, lush and green, so weeds don’t stand a fighting chance at taking over your lawn.
How To Overseed: The Step-By-Step Process, Explained
The first consideration, before you start overseeding your lawn, is choosing the right variety of grass seed. The best options are perennial varieties that will do well both in your geographical region as well as in your particular yard. If you have a yard with large trees and lots of shade, for example, a shade-tolerant variety like fescue might perform better than a different, sun-loving variety like Bermuda. Another thing to consider is how damp or dry your region is, and what type of drainage your yard has. If you live in a wet area or your yard tends to collect moisture, a grass like St. Augustine might fare better than it would in a hotter, drier or sunnier area.
Once you’ve chosen the right grass seed for your yard, it’s time to prep your existing lawn and soil for overseeding. Here are the easy, step-by-step instructions for overseeding your lawn:
- Before you start your overseeding project, it’s important to water your yard deeply. In the days leading up to when you plan to spread your new grass seed, give your lawn a good soaking, allowing water to penetrate up to six inches below the surface. This will give your turf a couple of days to dry out a bit before you begin overseeding.
- Pull up or otherwise remove any large weeds in your existing grass. Bigger weeds can simply be pulled up by hand, preferably from the roots. You can also use an herbicide if you choose; if so, just be sure to follow up with a second application three weeks later to ensure that any new weed growth is also killed off.
- Mow your existing grass. Using a collection bag attachment if your mower has one, mow your lawn as short as possible, preferably to about one and a half inches. Yes, this will make whatever healthy grass you have look bald and terrible for the moment—but don’t worry! There’s a method to the madness. Your new grass seeds are going to need access to sunlight and water as they take root and grow, so it’s very important to facilitate that by getting the existing grass as short as possible. Once you’ve finished mowing, rake up any leftover grass clippings and dispose of them in lawn bags.
- Remove thatch. Thatch is the criss-crossing layer of dead grass roots and stems that lies on top of the soil, just beneath the greener blades of grass. Thatch must be removed so that new grass seeds can reach the soil along with compost, fertilizer and water. In smaller yards, thatch can be removed effectively with a hand-held rake, but homeowners with larger yards may want to rent a power dethatcher from your local garden center to do the job. Also called power rakes or vertical mowers, these machines will leave clumps and piles of grass and thatch; be sure to rake debris up when you’re finished with this step and dispose of it in yard bags.
- Aerate your grass. You can rent an aerator from your local garden center or, if your yard is small (or you simply don’t like the loud noise and gasoline stench of an aerating machine), use a manual aerating tool. Be sure to rake up and dispose of any soil plugs that are dislodged as part of the aerating process.
- Spread a half-inch thick layer of compost over your lawn. Once you’ve got your compost spread evenly, rake it lightly so it can mix with the soil and blend into the aeration holes.
- Fertilize your grass. Grass fertilizers contain nitrogen, phosphorous and potassium—the three most important ingredients in a healthy lawn. You can use either a hand-held spreader for smaller yards or a drop spreader for larger ones to distribute your fertilizer evenly all over the yard.
- Apply grass seed. Using a hand-held broadcast spreader, apply your chosen grass seed over the entire lawn area. The goal is to have about 15 to 20 seeds per square inch, which typically results in several pounds of seed per 1,000 square feet of lawn. You can move in parallel lines as you spread the seed and then, if needed, go back over the area in perpendicular lines to ensure proper, even spreading.
- Use a rake to work the seed very lightly into the existing grass and soil. Be gentle—you don’t want to damage your seeds or interfere with their even distribution.
- Water generously, but not too much, and voilà—you’ve just overseeded your yard!
Over the next days and weeks as your grass begins coming in, be sure to water lightly once or twice a day, making sure the area doesn’t get sopping wet. This will give your lawn just the right amount of moisture until seedlings sprout. Let your new grass grow at least three to four inches before mowing for the first time. Once you’ve mowed the first time, you can switch to a deep-soaking watering pattern. To keep your grass its healthiest over time, be sure to fertilize twice every year, each spring and fall.
ABC Can Keep Your Yard Healthy And Green
Keeping your lawn healthy isn’t just a source of beauty and pride; it is also a practical measure for keeping weeds away. At ABC Home & Commercial Services, we know all about creating and maintaining dense, healthy lawns for our satisfied customers. If your lawn is becoming an eyesore and the overseeding process described above sounds like a little too much for you to handle, ABC is here to help. Our lawn specialists can reclaim and revive tired, weedy, patchy lawns and maintain thriving ones so your yard stays beautiful for years.
Seeding Your Lawn
An attractive lawn with minimum maintenance problems begins with proper site preparation. The initial investment should be considered over the many years that a correctly established and maintained lawn will provide enjoyment. For example, improper grading can increase mowing time and reduce turf quality. Drainage problems will encourage weed encroachment and wetter areas are difficult to mow. Research studies have demonstrated that the rapid germination and growth of turfgrass is critical for a successful lawn establishment.
Listed below are the major points to consider when planting a new lawn:
Establish a sloping grade, free of depressions, away from buildings. Naturally wet areas, due to internal drainage problems, should be corrected by the installation of a subsurface drainage system such as perforated pipe and stone. Remove all rough debris including large stones. The grade around established trees should not be altered to avoid damaging the existing root system.
It is important to properly prepare the soil. The following steps should be accomplished prior to seeding:
- Soil Testing: Make every effort to have the soil tested. Test results will provide an accurate recommendation of the specific lime and nutrient requirements for that soil. County Cooperative Extension Offices can assist in obtaining the soil testing kits and in the interpretation of the results.
- Liming: Proper liming is essential for maximum utilization of the applied fertilizer and other soil nutrients by the germinating turfgrass.
- Apply the recommended amount of lime and fertilizer and incorporate uniformly into the soil 4 to 6 inches deep.
- If the amount of lime required exceeds 200 pounds per 1000 square feet, apply one-half of the recommended amount, work it into the soil, then apply the remainder and incorporate into the soil.
- Preplant Incorporated Fertilizer: Evenly broadcast fertilizer or other nutrient source as recommended by soil testing and till into the soil 3 to 4 inches deep. (Can be done with liming).
- Post Plant (“Topdress”) Fertilizer: Following your incorporated application, a fertilizer should also be applied 2 to 4 weeks after turfgrass emergence. Apply 3 to 5 pounds of 20-10-10 fertilizer per 1000 square feet or the equivalent amount of 2-1-1 ratio fertilizer. Applying nitrogen containing fertilizer to young turfgrass seedlings promotes rapid lawn development. Consider watering in fertilizer if rain is not imminent. Do not apply fertilizer to “wet” grass seedlings as some types may cause plant “burn”.
- Timing: Late summer and early fall provide the most ideal conditions for turfgrass establishment. Generally, this timing will allow adequate grass growth prior to winter. Cool evening and moderate daytime temperatures, along with anticipated fall precipitation, are conducive to rapid seed germination. In addition, many weeds including crabgrass are no longer germinating, reducing competition in new turfgrass plantings.
- Primary Establishment Period—late summer, early fall. (The earlier date is most desirable.) Southern New Jersey (Trenton and south) August 20 to October 10 Northern New Jersey (Trenton and north) August 15th to October 5th.
- Secondary Establishment Period—early spring (all of New Jersey).
- Establish the lawn during the first warm, dry period as soon as soil is dry enough to till without forming clods. Preparing soil when it is too wet results in poor germination and growth from compacted soil conditions.
Use quality seed adapted to site.
Seed Selection: Many advances have been made by turfgrass breeders in recent years. For instance, there are now Kentucky bluegrass varieties better adapted to moderate shade, as well as improved disease resistance. Tall fescues, just a few years ago, were considered stemy, coarse grasses. Today, finer leafed, lower growing, denser and darker green tall fescues are available. The same can be said for perennial ryegrasses. Fine leaf fescues, such as hard fescue and creeping red fescue, are known for their adaptability to shady areas and “droughty” soil. New improved fine fescues are also available.
In addition, the issue of seed mixtures is an important consideration. Reputable seed companies provide mixtures of “improved” varieties of various species allowing a wider range of site adaptation. Mixtures of various turfgrass species, each selected for a specific trait, provide the best opportunity for successful lawn establishment if a site has a combination of wet, dry, sunny and shady areas.
- Kentucky Bluegrasses (Poa pratensis) This is a popular lawn grass in New Jersey. It is hardy, attractive, widely adapted and known for its pleasing color and leaf texture. New varieties have some shade tolerance and improved disease resistance. It is suitable for moderately to well-drained soil but is somewhat slow to establish from seed. Spreading underground rhizomes (stems) enhance recovery from injury and fill in voids. Seeding rate is approximately 2 pounds per 1000 square feet. Spring seedlings are difficult to establish.
- Tall Fescues (Festuca arundinacea) This is a coarser bunch-type grass able to persist in moderate to well-drained, infertile soils. Newer varieties are improved in leaf color, texture and density. Tall fescues are also known for rapid establishment from seed, excellent drought tolerance and ability to tolerate traffic. Seeding rates are 4 to 6 pounds per 1000 square feet.
- Fine Fescues (Festuca spp.) Fine fescues are comprised of several species (hard, sheeps, creeping red). As a group, they are known for their ability to persist in shady areas as well as in dry infertile locations. They establish slightly faster than Kentucky bluegrass. Improved newer varieties are useful for lower maintenance turfgrass areas. Fine fescues do not tolerate high traffic. Seeding rates are 4 to 6 pounds per 1000 square feet.
- Perennial Ryegrass (Lolium perenne) Breeding advances have produced varieties markedly improved over the older non-persistent types. These newer turf type ryegrasses have excellent color and fine textured leaves. They survive in a wide range of soil conditions but grow poorly in extremely wet areas. They possess moderate shade tolerance and very rapid establishment. Seeding rates are 4 to 6 pounds per 1000 square feet.
Rapid Lawn Establishment: At certain times, such as in new home construction where dust or muddy conditions cause concern or on sloping terrain where soil erosion is a serious problem, a rapid cover of turfgrass is most critical. A first choice may be sodding the critical areas (see Rutgers Cooperative Extension fact sheet FS104, “Steps to an Instant Lawn”). Another choice can be the use of seed mixtures containing primarily perennial ryegrass or tall fescue. These varieties in combination with the use of straw mulch (see next point) and timely rainfall or irrigation can provide an “established” lawn in 4 weeks if growing conditions are favorable.
Clean straw mulch conserves moisture.
Straw Mulching and Irrigation: It is desirable to keep newly seeded lawns moist in the top 2 inches through irrigation or rainfall. If the top layer of soil dries out prior to good root establishment, poor stands of turfgrass may result. Some temporary surface drying is acceptable but should be kept to a minimum until germination is complete. Once seedlings have an established root system, watering can be less frequent and deeper (3 to 5 inches). Irrigation should not be overdone (do not create constant “muddy” conditions). Observe the drier areas of the lawn (sunny, high areas) for early signs of wilting. Irrigate, if feasible, to increase chances of successful establishment.
Straw mulch such as unrotted, weed seed free wheat, oat, rye, or salt hay can be applied at 50 to 90 lbs., (1 to 2 bales) per 1000 square feet. This offers a significant advantage for turfgrass establishment. Light mulching, where approximately 25% of the soil is visible through mulch, is all that is needed in most situations.
Mulching increases soil moisture retention. Morning dew is retained longer on the soil surface. Benefits include reduced watering needs and quicker seed germination.
Weed control in newly planted turfgrass.
The author wishes to thank J. Heckman, R. Duell, R. Funk, J. Murphy, B. Clarke, and E. Milewski for their constructive inputs into this fact sheet.
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How to Overseed or Reseed Your Lawn
There’s a secret behind achieving a beautiful, lush lawn. Landscape professionals know what it is, but many homeowners don’t. Overseeding—as part of a comprehensive, proactive plan—keeps lawns looking great. Whether you’re tending your first lawn or have years of experience, learning how to overseed your lawn can improve your results.
Overseeding is spreading grass seed over an existing lawn. Done right, it’s a straightforward process that gets results. As grasses mature, thinning is normal—especially if you enjoy your lawn and use it often. Overseeding keeps your lawn competitive and steeped in youth and vigor, without starting over from scratch.
The basics of overseeding are the same everywhere, but goals and timing vary based on geography and the type of grass grown. For success with overseeding your lawn, follow this basic guide:
Establish Your Goal
Homeowners overseed to correct thin lawns, but pros overseed to prevent thinning. For lawns in southern regions, overseeding warm-season grasses with cool-season reinforcements adds green color during winter. When warm-season grasses go brown, overseeding with a premium, cool-season ryegrass, such as Pennington Annual Ryegrass, provides a green temporary lawn while your permanent, warm-season grasses are dormant.
Time the Task
The best time for planting cool-season grasses in northern regions is late summer to early fall, when they’re growing most vigorously. Spring is the second best time. The warm soil encourages seed germination, cool fall air stimulates growth, and soil moisture stays more constant. Tough, warm-season lawn weeds, such as crabgrass and nutsedge, are less active in fall, too. The Turfgrass Water Conservation Alliance service recommends overseeding at least 45 days before your average first fall frost. 1 In southern areas, overseed thinning lawns in late spring, as warm-season grasses enter active growth. For winter color, overseed southern lawns in fall. Wait until nighttime temperatures drop consistently below 65°F and your existing warm-season lawn slows and begins to lose color.
Prepare the Area
Mow your lawn extra short and remove the clippings, so new seed contacts soil and gets sunlight and water. Set your mower at two inches or less for regular overseeding. For southern lawns and winter color, set the blade as low as it goes, and cut just above the soil—what’s known as scalping. Rake the soil with a metal thatch rake to remove thatch, clippings and debris. This loosens and exposes soil to receive seed.
Correct Existing Lawn Problems
For troubles beyond normal thinning, test your soil and make corrections before overseeding. Follow test recommendations for using soil amendments and repairing bare lawn spots. If needed, take time to dethatch and core aerate compacted lawns so air, moisture and seed can get to the soil. Pennington One Step Complete products combine premium seed with a stabilized-release fertilizer and wood mulch to simplify lawn repairs.
Select a Quality Grass Seed Product
Better seed yields better lawns. Always use grasses recommended for your regional climate and choose top-quality grass seed you can depend on. Pennington Smart Seed products provide premium grass seed appropriate for sun, shade or high-traffic areas in lawns in northern or southern regions. Three-in-one Pennington Lawn Booster combines superior Smart Seed varieties with premium-grade fertilizer and soil enhancer.
Spread Your Seed
Apply seed at label-recommended overseeding rates, using the lawn spreader that suits the job. Use drop or broadcast spreaders for large lawns and handheld spreaders for smaller areas. For small spots, simply seed from your hand. Work when the air is calm, so seed distributes evenly.
Fertilize Overseeded Areas
Avoid weed & feed products; the pre-emergent herbicides inhibit seed germination. Starter fertilizer, such as Pennington Ultragreen Starter Fertilizer 12-22-8, delivers essential nutrients for new grass. Phosphorus supports vigorous root growth, while nitrogen fuels top growth and greening. Some states and counties restrict phosphorus lawn fertilizers due to environmental concerns regarding runoff, but exceptions may be made for new seedings. Check with your local county extension agent about nutrient application restrictions.
Keep Your Lawn Well-Watered
Newly overseeded lawns need consistent moisture. Keep seed and soil moist with frequent, light waterings twice a day for the first four days; water more heavily every other day for the next five days; then water as needed to prevent wilting. This encourages deep, healthy roots.
Return to Regular Maintenance
Keep your newly revived lawn looking its best with a regular, comprehensive maintenance plan that includes diligent watering, best mowing practices and proactive overseeding. A simple weekday lawn maintenance schedule can keep your lawn lush and your weekends free.
For a simple, all-in-one approach to a thicker lawn, you can put your lawn on the fast track with Pennington Lawn Booster. This easy-to-use product simplifies overseeding to give your lawn the boost it needs. In just one application, your lawn will grow quicker, thicker and greener than ordinary grass—guaranteed.
Available in formulas for sun & shade or tall fescue lawns, Lawn Booster combines three essentials: seed, fertilizer and soil enhancer. Lime-enhanced, pure-bred Pennington Smart Seed, backed by years of breeding and research, adds beauty and sustainability. Once established, these water-conserving grasses require up to 30 percent less water than ordinary grasses. That’s year after year, for the life of your lawn. Plus, they stay green up to three weeks without watering. That means less work and more leisure time for you.
The premium fertilizer in Lawn Booster stabilizes nitrogen in the soil, to reduce leaching and other nitrogen loss to the environment. Your seed gets nitrogen for immediate feeding and for extended feeding for up to eight weeks, without extra fertilizer inputs on your part. Moreover, the soil-enhancing gypsum in Lawn Booster corrects soil conditions to allow for better root growth, so your newly boosted lawn can flourish and be the talk of the neighborhood.
For the lawn of your dreams, don’t wait to overseed until your lawn looks less than its best. Give your lawn the boost it needs, step-by-step or all-in-one. Pennington’s here with premium grass seed and lawn care products to help you keep your lawn at its peak.
Pennington, One Step Complete, Smart Seed, and Ultragreen are trademarks of Pennington Seed, Inc.
Turfgrass Water Conservation Alliance is a registered trademark of NexGen Turf Research, LLC.