Planting (or seeding) a lawn is not difficult. It is a simple DIY procedure that can be done successfully by anyone who chooses to. But can you seed a lawn that already has grass? The answer is yes, you can seed a lawn that already has grass too.
It is more or less the same as planting grass seed. However, unlike simple planting that is done for new lawns, this is often done to create a lush lawn, make the lawn thicker, and remove any unwanted spaces where initial seeds might have done poorly.
WHEN SHOULD YOU SEED A LAWN THAT ALREADY HAS GRASS?
The act of seeding a lawn that already has grass is called overseeding. It’s the planting of grass seed directly on existing turf, without tearing the turf or soil. Overseeding is an easy way to improve the density of turf, fill in bare spots, and enhance your lawn’s color. The best time to overseed your lawn is often during the fall. However, depending on the grass type on your lawn, overseeding in the spring can often yield great results too.
If you prefer overseeding your lawn during the spring, do so early so you can give your seedlings enough time to mature before the onset of the summer’s heat. Remember it takes grass 5 – 30 days to germinate depending on the type. In cooler areas, it could take longer than this so be sure first.
HOW DO YOU SEED A LAWN THAT ALREADY HAS GRASS?
Like we have said before, seeding a lawn is usually a simple DIY procedure. And the truth is, a great lawn can only come from great grass seeds. The same applies to an overseeded lawn. Here is how to seed a lawn that already has grass.
FACTORS TO CONSIDER WHEN YOU SEED A LAWN THAT ALREADY HAS GRASS
Top quality grass seeds for overseeding purposes should be NTEP rated variety. This simply means that you are using seeds that have been specifically bred for superior grass qualities in terms of color, disease and drought tolerance, and insect resistance.
How much seed is needed to overseed a lawn? Check the amount that is specified in the seed packaging. Use standard seed application capacity. Too many seeds too close together cause seedlings to fight for room and the existing nutrients. This will leave grass looking weak or thin in these areas where you seed a lawn that already has grass.
Watering lightly but frequently aids the germination of new grass seeds. It also allows the quick penetration of grassroots and keeps the lawn looking green and lush. Water at least once a day when temps are cool, this can be done in the morning or late evening.
The best time to seed a lawn that already has grass is during the fall for cool season grasses. You can also overseed very early in the spring. Do not overseed during the summer as too much heat kills grass seeds.
It is important to know the germination period of your grass. This will determine the right time to overseed. The standard germination time frame is usually 5 – 30 days. Just know what your grass takes. Ask the grass seed vendors.
Grass clipping is removed to allow new seeds to come into contact with the soil and to get enough sunlight and water. The standard mowing before overseeding is usually two inches or less. However, for southern lawns and winter color, it is recommended that you do scalping (set the blade as low as it goes while cutting just above the soil level).
WHEN CAN YOU MOW AN OVERSEEDED LAWN?
Many people are often worried of when they can mow the lawn after overseeding. Well here is what you know, you should begin watering your lawn right after you overseed. Do this once or twice a day especially during the cooler parts of the day until your grass grows to mowing height.
WHAT DIFFERENCE DOES SEEDING HAVE FROM OVERSEEDING?
To know how to seed a lawn that already has grass, you should understand the difference between seeding and overseeding. Seeding is simply the opposite of overseeding. While overseeding is done on a lawn that already has grass, seeding is done on an entirely new lawn with no signs of existing grass. Here are the main differences.
CHOOSE THE RIGHT GRASS SEED TO GROW A HEALTHY LAWN
If you want to know how to seed a lawn and choose the right grass seed, consider the following:
Choose between Warm-season Grasses and Cool-season Grasses
Grass falls into two categories: warm-season and cool-season. Warm-season grasses grow in warmer regions (southern regions of the US). These include grasses such as Bermuda, St. Augustine, Centipede, Buffalo, and Zoysia. Warm-season grasses achieve peak growth in summer, as they require sunlight to thrive.
Cool-season grasses grow in northern regions of the US. Fine Fescue, Tall Fescue, Red Fescue, Kentucky bluegrass, and perennial Ryegrass are examples of cool-season grasses. This type of turf achieves peak growth during spring and fall. These grasses are more shade-tolerant (especially the fescues).
Wear and Tear
One thing to consider when selecting a grass seed is how much wear and tear the lawn will be experiencing. If you have children who enjoy running on the lawn, opt for a grass other than Fine Fescue, as it doesn’t stand well to foot traffic. Kentucky bluegrass is ideal for athletic fields because it is self-mending. When there is damage, the grass will creep in to fill in holes. The downside is, Kentucky bluegrass is more demanding when it comes to caring, mowing, fertilizing and watering.
If you live in an area prone to water restrictions or droughts, choose a grass like Tall Fescue, Buffalo grass, or Zoysia. Floratam is a variety of St. Augustine that is drought-tolerant but requires some shade. Meanwhile, if you intend to plant Kentucky bluegrass, you’ll need to water them regularly to maintain a healthy lawn.
Consider lawn maintenance when choosing grass seed. Fescues don’t need mowing as often as Kentucky bluegrass. Among warm-season grasses, you’ll need to mow Bermuda grass and Centipede more frequently than Zoysia. Buffalo grass requires the least amount of mowing. Also, turf which goes dormant in summer or winter requires less mowing during the period of dormancy.
Fertilizing Your Lawn
If you want an eco-friendly lawn and like the idea of organic fertilizing, make sure your choice of grass responds well to that. Some turf needs more frequent fertilization. Don’t plant a high-maintenance grass if you cannot devote time to take care of it properly. Regardless of the type of grass seed you buy, the weed seed content should be less than 1%, while the inert material content should be less than 4%.
WHEN SHOULD YOU SEED A LAWN?
Proper timing is essential when seeding a lawn. Decide whether you want a cool-season grass or a warm-season grass. Consider where you live when choosing the type of seed to plant in your lawn. In the US, cool-season grasses thrive in the north, while warm-season grasses flourish in the south. A region between the northern and southern US is referred to as the “transition zone,” where mixes or cool and warm-season grasses typically flourish.
Depending on local conditions, you should seed cool-season grasses such as Fine Fescue, Tall Fescue, Bentgrass, Ryegrass, and Bluegrass in mid-August through mid-October. These types of grass thrive in temperatures above 60°F (16°C) and become dormant when temperatures fall during winter.
On the other hand, warm-season grasses such as Bermuda, Bahia, Carpetgrass, Centipede, Zoysia, and St. Augustine, should be seeded from March to September, depending on local conditions. These types of grass thrive in temperatures above 80°F (27°C) and require less water, making them more drought-resistant.
HOW TO RESEED
Overseeding is a good option to enhance your lawn. However, if your grass is in poor shape or your lawn is full of weeds, consider establishing a new healthy lawn by reseeding or starting over from scratch. Follow these steps:
Get a soil analysis
Before spending money on grass seed, it’s essential to test your soil first. Even if you select the ideal grass seed but your soil pH is incorrect, you might end up with a lackluster lawn. Most turf grasses thrive in well-aerated soil with a slightly acidic pH (6 to 7.5). You can obtain a soil test kit from the local extension office. Then, gather soil samples from three different locations in the area you will be seeding. Remove any rocks or grass, mix the soil, and put the soil into the testing bag. It can take two weeks before you get the results.
Kill existing grass
You can kill existing grass with a non-selective herbicide like Roundup. But if you don’t want to use chemicals, you can rent a sod cutter which is a machine that removes strips of grass with the roots and soil attached. You can also kill existing grass by blocking out sunlight with a black poly film. Remove it when the grass is already dry and brown, which may take 2 to 3 weeks, depending on the weather.
Remove the dead stuff
Now comes the full body workout: Rake up dead grass and weeds before you amend the soil. You have to do it for this reseeding lawn project.
Improve the soil
Spread the soil conditioners across the entire lawn. Till them into soil at a depth of about 5 inches.
Smooth the soil
Grass seeds need smooth and level ground for ideal growth. To achieve a good seed-to-soil contact, remove rocks and debris, then smooth the soil with a broom rake.
Add a starter fertilizer
A starter fertilizer gives seeds the nutrients it needs to grow quickly. You can consult with a local nursery to determine the best starter fertilizer for your chosen grass seed. Make sure to follow the instructions on the bag before applying the fertilizer.
Pick seed to match your site
Consult with a garden center to choose a seed that will match your site conditions, lawn care preference, and budget. Ask about low-maintenance and drought-resistant varieties. Purchase grass seeds by the bag or in bulk. But only buy what you need. Too many seeds can reduce germination rate.
Prepare the seed
Pour the seeds and fertilizer into a plastic bucket and mix thoroughly.
Spread the seed
Load the seed into a spreader and apply it for the reseeding lawn work. Rake to cover the furrows. Compact the soil with a sod roller to get good seed-to-soil contact.
Add mulch or grass seed accelerator
Cover the soil surface with compost mulch or apply a grass seed accelerator. An accelerator absorbs more moisture compared to mulch or hay and slowly releases it. It degrades naturally, eliminating the need for cleanup.
Water, but not too much
Water the lawn generously after the mulch application. Stop when you see puddles forming. For the best results, keep soil moist to a depth of 4 to 6 inches. Water regularly as the seedlings grow. Gradually reduce watering over a 6-week period. Then switch to a normal watering routine.
Cut the grass
Mow the new lawn when it reaches a height of 3 inches. Set the cutting height to 2-1/2 inches. Use a newly sharpened blade; it is beneficial for the grass. Avoid using a dull blade as it can rip the grass.
FINAL THOUGHTS ON HOW TO SEED A LAWN
To seed a lawn that already has grass successfully, just make sure that you keep the top ¼ inch of the soil moist. It will allow the seed to stay moist always. This should spur quick germination. Also, ensure that you cover the entire overseeded area thoroughly each time to support root growth for your newly overseeded lawn grass seeds.