Adjust Your Expectations
Lawn chemicals do work, and it's difficult to get that flawless 'golf course look' without them. So if you plan to eliminate or drastically reduce chemical use, you may have to accept imperfections. Expect a dandelion or two and areas that will be a little less green at some times of the year. That said, you could still expect your lawn to look good?probably as good or better than most of your neighbors' lawns.
Mowing is a chore that's easy to put off?the grass will still be there in a couple days. But delay is bad for your grass. The taller it gets, the more you'll cut off when you finally mow. And the more you cut off, the more you'll 'shock' the grass. That weakens each individual plant and leads to other problems later on. It also opens up the turf canopy and allows weeds to bully their way in.
Rule of thumb: Never remove more than one-third of the leaf blade each time you mow. And keep your lawn mower blade sharp. A clean cut reduces the chance of common lawn diseases making their way into the leaf tissue. Your lawn will look much better too.
Thatch is a layer of slowly decomposing grass stems, roots, clippings and debris that accumulate at the soil surface over time. It can build up in your lawn and virtually choke it to death. Excessive thatch buildup is commonly found in lawns that have been overfertilized or overwatered and have never been aerated. Thatch buildup of 3/4 in. or more will restrict water and nutrient penetration into the soil (think thatched roof) and can harbor disease organisms that can increase the need for pesticides. Slice open a section of turf. If the thatch is more than 3/4 in. thick, take action.
Regular core aeration will slow thatch development. However, it won't do much to remove existing thatch. This can be done by renting a power rake, which will 'lift' the thatch from the soil surface. This thatch residue can then be raked by hand and removed. Dethatching is hard work, so it's smart to prevent buildup in the first place. The best way to do that is to avoid overwatering and overfertilizing.
Top-dress your lawn with high-quality compost. Compost can bring depleted or damaged soil back to life, resulting in stronger root systems and happier plants. One teaspoon of compost contains a billion beneficial microorganisms that help create better soil structure and texture, which improves nutrient, water and air retention.
To apply compost, spread it over your lawn with a shovel, aiming for a layer 1/4 to 1/2 in. thick. Then work it into the turf with a rake. It's best to do this after aerating. Most garden centers sell bagged compost. But to cover an entire yard, you're better off buying in bulk from a garden center. Don't worry about buying too much?any leftovers will benefit your garden and shrub beds.
Instead of applying costly pesticides, sow quality grass seed. Reseeding your lawn every year will help maintain good turf density and make it very difficult for weeds to take hold and grow. In fact, some grasses actually release a beneficial toxin into the soil that acts like a natural preemergent herbicide, preventing weeds from germinating.
Reseeding with genetically improved varieties will also boost your lawn's performance. Many newer grasses require less fertilizer, watering and mowing compared with the older grasses that are most likely in your lawn. If you haven't reseeded in the past 10 years, you're long overdue. Simply use your fertilizer spreader to broadcast seed immediately after core aerating. Those soil plugs lying on your lawn's surface will dry out while you do this. After you've spread the seed, break up these cores with a rake. The combination of seed and pulverized soil will backfill your aerator holes, creating perfect seed-to-soil contact.
Fertilize Just Enough
Regular composting doesn't replace fertilizing. Your lawn will still require food once in a while. And testing your soil (every two or three years) is the best way to know when and how much fertilizer your grass needs. It will help you determine nutrient deficiencies and excesses, so you won't pay for or apply fertilizer you don't need. Don't fertilize because you think your lawn needs it. Contact your local university or garden center for help with soil testing.
There's no need to fertilizer more than twice a year. An organic fertilizer applied after core aeration will maximize plant and soil health. Like compost, organic fertilizers help feed beneficial organisms and replace valuable nutrients in your lawn. Most organic fertilizers are very safe to use nearly any time of the growing season. We prefer meal-based organics containing bonemeal, blood meal, fish meal and feather meal; however, organics made with poultry litter and biosolids work too.
One of the biggest mistakes made by lawn owners who have a sprinkler system is overusing it! Too much water is costly, wasteful and bad for your lawn. Water early in the morning, not during the afternoon when it's hot or when it's windy. More of that precious water will make its way to the roots.
Space irrigation cycles as far apart as possible. Let the grass wilt and turn a little blue before watering again. The less you water, the deeper those grass roots will go to look for it. This is a good thing! Overwatering discourages roots from penetrating deep into the soil. They are encouraged to stay close to the surface where the moisture is. A lawn with shallow roots dries out quicker. Not good!
Raise Your Mower
Taller grass means a healthier lawn. It shades the soil surface, keeps the soil from drying out and reduces watering needs. Shaded soil also makes it harder for weeds to get started. If you raise your mowing height, you may even find that the taller grass chokes out existing weeds. For northern lawns, 3 in. is a great target height. For warm climates, 1-1/2 to 2 in. is best.
Aerate the Soil
'Aerating' simply means making holes in the ground by removing plugs of soil. And it's the single most important task you can perform to maintain a healthy, good-looking lawn. Nothing else comes close! It relieves compaction caused by foot traffic and creates extra pore space in the soil, allowing air, nutrients and water to enter. All of that helps roots to thrive.
Aerate your lawn at least once a year, preferably in the fall. Do it two or even three times each year if you can. The more, the better. You can rent a lawn aerator at any equipment rental store. Get one that will remove plugs of soil rather than one that pokes holes in the ground.
Grass is a sun-hungry plant. By strategically removing a few branches or carefully trimming lower limbs, you'll give it more sunlight. This can also improve air circulation, which helps cool your lawn during hot, humid conditions and reduces lawn diseases. In many cases, your trees and shrubs will look better too. If you love your trees and shrubs just the way they are, consider replacing grass with shade-tolerant ground covers or decorative mulch. Remember: You can't have both deep shade and lush grass.