Our staff expert tells you the six secrets for growing greener grass. You'll keep your lawn healthier, greener and thicker with a lot less effort. He also reveals the five biggest mistakes!
Travis Larson, lawn turf expert
As the in-house turf “expert” at The Family Handyman for the past 15 years, I’ve spent a huge amount of time talking with world-class grass gurus and learning the science of lawns. And I’ve spent even more time clearing and converting a half-acre of rough, overgrown horse pasture to a Pebble Beach–quality lawn. My final conclusion is this: Growing greener grass is surprisingly simple and easy. If you’re willing to learn some basic facts and put in just a few hours of light labor every summer, you can have a lush lawn. You supply the labor and we will the know-how where you can learn how to grow greener grass.
Water for 30 minutes. Then plunge a spade into the soil and pry out a wedge to see how far the water has penetrated. Four to 6 in. deep is ideal. Not deep enough? Water longer. Once you know how long to water, use a water timer and you’ll know what to set it for every time.
If you water frequently and for short periods, the grass roots have no reason to grow deep. Those shallow roots can’t reach deep soil nutrients or deliver the water when you skip a watering. Instead, water deeply enough to penetrate the soil 4 to 6 in. Do our little test for a few waterings and you’ll get a sense of just how long and often. It’ll depend entirely on weather conditions and your soil type.
Heavy soils should be watered less often and less heavily but for longer periods of time. Sandy soils, on the other hand, can handle heavy, fast watering but dry out faster. In hot, dry weather, you may have to water every two to three days.
You need to kill weeds when they’re growing. That’s because the herbicide is absorbed through the leaves and then sent throughout the rest of the plant. When the weather is too cool, the weed isn’t growing and the herbicide won’t be absorbed, and the chemical isn’t as effective. Too hot and the herbicide will stress the grass. The product directions will give you the best temperature range. Apply herbicides when rain isn’t forecast; a soaking will just rinse off the herbicide before it can do any good.
Spread crabgrass preventer between the second and third mowings to knock out crabgrass before it sprouts.
Crabgrass preventers (aka pre-emergence treatments) do one thing and one thing only. They prevent crabgrass (and any other seed) from sprouting. Once crabgrass sprouts, it’s too late. Here’s the key. Apply preventer between the second and the third mowings. Because crabgrass starts sprouting a few weeks after the grass greens up, that’s generally just the right time.
Set the lawnmower cutting height to match the ideal cut length of your grass type.
Illustration courtesy of Trevor Johnston
Every grass type has an optimal cutting height. And you’re better off on the high side of that height. Here are a few reasons. The grass blade is the food factory of the plant. Short blades just can’t generate as much food as long blades. Long blades also shade and cool the soil. That means weed seeds are less likely to sprout, and you won’t have to water as often because water won’t evaporate as fast. Not sure what type of grass you have? Take a sample to a garden center for help. Or go to scotts.com and click on “grass type identifier” at the bottom of the page. Compare your sample with the ones shown.Learn how to mow the lawn to the right height in our video tutorial.
Before the lawn goes to sleep for the winter, you should feed it well. Even after the grass seems to go dormant, the roots are soaking up nutrients and storing energy for the next growing season. Surprisingly, it’s much more important to fertilize in the fall than in the spring, when most people do it. Like watering, this is one of the most important favors you can do for your lawn.
Grasses like a pH level between 6 and 7.2.
Illustration courtesy of Trevor Johnston
Grass grows best when it’s growing in the “pH happy zone.” If the soil is too acidic or too alkaline, the grass won’t thrive even if you do everything else right. So collect one tablespoon-size sample a couple of inches under the sod in three different places in your yard and take the three samples in for testing. Some garden centers offer the service, or search the Internet for “soil testing” to find a place to send it.
You’re after a pH between 6 and 7.2. If it’s too high, you’ll treat the lawn with iron sulfate or sulphur; too low and you’ll use pelletized limestone. Whoever does the testing will tell you what and how much to use to fix the pH. Applying the treatment is as easy as walking around the yard with a spreader.Learn how to correct soil PH in our video tutorial.
A broadcast spreader delivers more consistent coverage than a drop spreader.
Use a broadcast spreader—not a drop spreader. Drop spreaders (the type that drops granules straight down) are notoriously tricky to use. You’re bound to end up with stripes or checkerboard patterns on your grass. You’re much better off with a broadcast spreader, which spews out the granules at random for much more consistent coverage.
Use a small pump sprayer to eliminate the few leftover weeds.
Don't treat your whole lawn for just a few weeds. That's expensive, a hassle and ecologically unsound. If you have only a few weeds, pull them by hand or spray each one with a pump-up sprayer.
A hose-end sprayer with liquid weed-killer is a fast and effective solution for a lawn filled with weeds.
Use a hose-end sprayer to kill a yard full of weeds. It’s faster and more effective to dispense concentrated liquid broadleaf killers than to use granular broadleaf killers. You just add the herbicide, dial in the right concentration on the sprayer lid and walk around the yard and mist all the weeds. You can treat an average yard in less than 20 minutes.
Reseeding works best during cooler, damper weather.
Reseed in the late summer/early fall. Whether you’re seeding a small patch or a whole yard, you’re going to be much more successful if you wait for the cooler, damper weather of late summer or early fall. It’s almost impossible to get seed to survive during the dog days of summer. It’s simply too hot and dry. You’ll most likely just waste your time and expensive seed.
Concentrated liquid weed killers cost less in the long run than premixed weed killers.
Use concentrates whenever you can. For most liquids, you can buy concentrates and mix your own treatment with water. You'll save about 70 percent of the cost of premixed. Be sure to mix only as much as you can use within a week or two. Minerals in tap water will reduce the potency of the chemicals in just a short time.
Dethatching involves flailing away at your lawn with a powerful, engine-driven steel rake. If that sounds scary, imagine how your grass feels! The idea is to rake up the old woody stems resting at the base of the grass leaves. Dethatching does this, but at great cost to your lawn because it tears up not only the grass but also the roots. It’s rarely a good idea. If you have thatch, it’s probably because you’ve been underwatering, overfertilizing and/or consistently mowing when the grass is overgrown.
Mow frequently and let the grass clippings build better soil conditions.
OK, maybe it won’t actually wreck your lawn, but you’re not doing it any favors either. Let the clippings lie. They’ll release nutrients into the soil and form a mulch to help keep in soil moisture.
Be sure to read and follow the directions on the fertilizer bags and other lawn treatments.
They are SO important! It’s not only the concentration for fluids or the spreader setting for granules. Pay attention to the details like the rain forecast and what temperature ranges the treatments require. Skip them and you’ll either wreck your lawn or waste your time and money.
Yep, just skip the directions and pour it on. You'll kill your whole yard in no time. And if you don’t kill it outright, it'll turn yellow and take weeks to heal itself.
Sharpen your blade annually. It should shear the grass blades cleanly.
Dull mower blades rip through the leaves, which stresses the plant. Instead, you want to slice them off cleanly. You can always tell a lawn that’s been mowed with a dull blade because it looks brown on the top. Get on your hands and knees and you can actually see the damage.
1. Don’t mow wet grass. You’ll leave giant clumps of sodden clippings where they’ll smother the grass beneath. Not only that, it’ll carpet the underside of your mower deck with a thick mat.
2. Set your spreader at half the recommended dosage and treat the lawn twice from opposite directions. It’ll take twice as much hoof work on your part, but you’ll get a more consistent distribution.
3. Fill the spreader on the driveway, not over the grass. Or at least spread a tarp on the grass to catch spillage. If you have an accident, you’ll have a nice, big dead spot in your lawn.
4. Accept that you can’t grow grass everywhere. If you’ve struggled mightily to grow grass in a shady spot, at some point give it up and mulch, use a shade-tolerant ground cover or plan yourself a patio.
5. Give crabgrass a second dose of crabgrass preventer. About one month after your first treatment, apply a second to stop the seeds that survived the first treatment from germinating.
6. Rinse out your spreader every time, especially after using fertilizer. Fertilizer is essentially a type of salt. And it eats up any metal parts it finds.
7. Aerate in the Fall if you have heavy loam or clay soil. (No need if you have sand.) Just before you fertilize, rent an aerator and aerate the lawn from both directions. It will help loosen the soil and allow the fertilizer to penetrate deep into the soil.
8. Give your lawn a good flat-top for winter. Just this one time each year, set your lawn mower to 1-1/2 to 2 in. and clip it off. That’ll help retard mold during the winter.
9. Water new seed lightly and twice a day or more. If you don’t bother keeping the soil moist over new seed, don’t bother seeding. Dampen the soil even more often during hot, windy weather. Keep watering for at least two weeks and don’t miss any days.
10. Rake up downed leaves in the fall or those soggy leaves will suffocate the new sprouts in the spring and leave dead spots all over your lawn.
11. Choose “slow-release” fertilizers. Rather than feeding the lawn all at once, this type allows the lawn to snack over a longer period. These fertilizers cost a bit more but are well worth the added expense.
12. Don’t apply too much seed. You should try to achieve a concentration of about 15 seeds per square inch. If you exceed this, you’ll have an overpopulated lawn with too many plants competing for nutrients and sunlight.