Growing a thick patch of grass is easier than you think. A lot easier. You build the soil, grow the right grass for your conditions, feed it the natural way, and your lawn will be lush and lovely, and able to out-compete weeds.
Start with the soil
Grass grows best in soil that is high in organic matter (which is made up of dead plants in various stages of decay). Organic matter helps sandy soils hold water and nutrients. It prevents the compaction of clay soils. (Compacted soil is so dense that water can’t drain from it properly and oxygen can’t reach plant roots.) In every kind of soil, organic matter nourishes microorganisms and they make essential nutrients available to grassroots.
How do you increase the organic matter in your soil? Two very simple ways
First, when the leaves fall from the trees, don’t bother to rake them up. Instead, chop them into small pieces by running over them with the lawnmower; then let them rest in peace. You’ll be surprised by how quickly they break down and disappear. (See, we promised you less work.)
Second, leave the grass clippings on the lawn when you mow. As they decompose, they contribute nitrogen (the nutrient that makes grass grow thick) to the soil—almost 2 pounds of nitrogen per 1,000 square feet of soil each season—which you’d otherwise have to add with fertilizer. Grass clippings add a lot of organic matter to the soil.
Don’t believe people who tell you that clippings left on the lawn contribute to thatch, a layer on top of the soil that blocks moisture and oxygen from reaching plant roots. Just the opposite is true: Fresh clippings stimulate earthworm activity, which breaks down thatch. Overfertilizing is the most common cause of thatch.
Leaving grass clippings on the lawn is the best and most effortless thing you can do to grow a thicker, healthier lawn. William Dest, Ph.D., associate professor emeritus of turfgrass studies at the University of Connecticut, compared lawns where the clippings had been left behind with lawns where they had been removed. He found that the lawns with the clippings had:
- 45 percent less crabgrass
- Up to 66 percent less disease
- Up to 45 percent more earthworms
- 60 percent more water reaching plant roots
- 25 percent greater root mass (which means less room for weeds and more drought tolerance for grass)
- 50 percent reduced the need for nitrogen fertilizer
Feeding the Lawn
Organic matter regularly added to the soil provides many, but not all, of the nutrients your turf needs. So you may also want to apply granular organic lawn fertilizers, which are sold in most garden centers or you can order it from Amazon Store!
Organic fertilizers decompose and release their nutrients more gradually than synthetics and thus nourish the turf more steadily over a longer time. That keeps the grass from going through growth spurts, forcing you to mow too often and making the grass susceptible to disease.
The optimal times to spread fertilizer on your lawn are in early and late spring and early fall. In areas where lawns grow year-round, fertilize in late fall or early winter, too.
Go easy on the nitrogen: Spread no more than 1 pound of nitrogen per 1,000 square feet at any one application, and give the grass no more than 4 pounds per season. (To help you calculate: 20 pounds of fertilizer with 5 percent nitrogen will deliver 1 pound of actual nutrient.) As we said, grass clippings left on the lawn also contain nitrogen, so apply just 2 pounds of supplemental nitrogen if you’ve been leaving the clippings behind.
Cut High your Lawn
Another simple way to help your lawn grow up healthy and thick is to adjust your mower’s cutting height to its highest setting. Why? Tall blades of grass have more surface area exposed to the sun, enabling them to photosynthesize more sugars and starches for greater root growth. Greater root mass means better access to water and nutrients, so plants are more tolerant of drought and can recover more rapidly from dormancy. Tallgrass also outcompetes annual weeds and conserves moisture by shading the soil.
Most grasses can be mowed to a height of 31/2 to 4 inches. Some varieties, particularly fine fescues, and centipede grass fall over at that height and should be mowed a half-inch to an inch shorter than other grasses.
No matter how tall the turf, refrain from cutting off more than one-third of each grass blade in any single mowing, or you risk stressing the grass. And cutting off just one-third will produce small clippings that decompose quickly.
Planting a new lawn
In the North, fall is the best time to sow a new lawn because annual weeds are finishing their life cycles and are less likely to compete with new grass. Young turf plants can easily handle cool fall weather as long as they are six to eight weeks old before the first hard frost. It’s a different story in the South: Fall is a poor time for sowing grass there because southern weeds operate on a different schedule—many of them germinate in the fall. In the South, sow grass seed or put down sod after the soil warms in spring.
What if you move into a new house when it’s not an ideal sowing time? You don’t want to live in the middle of dirt patch while you wait for just the right time. Plant an interim lawn to fill in until you plant your permanent grass, suggests Warren Schultz in The Chemical-Free Lawn (Rodale Press, 1989).
In the North, annual ryegrass makes a good temporary lawn, Schultz reports. It germinates quickly, grows steadily, and covers a lot of ground. Ryegrass will die off over the winter, but by then its job will have been done. You can either till under the ryegrass in the fall and plant a permanent lawn in its place, or let it winterkill, rake out the dead grass, and overseed with a permanent seed mix early in the spring.
In the South, you can sow warm-season grasses from April to August. At any other time, start a cool-season nurse crop, such as perennial ryegrass, Schultz advises. The nurse crop of ryegrass will germinate quickly in any region. It will cover the ground and keep weeds from taking. If you till it in before planting a new lawn, you get a second benefit—the rye acts as green manure, adding organic matter to improve the soil. Which is where your lawn gets its start.