Q: What sort of lawn prep should I do before winter to get a jump start on next year's growing season? —Dave Krocak, St. Louis Park, Minn.
A: Roger Cook replies: With summer's heat and dryness at an end, September is the best month to lay the groundwork for next year's lush lawn. Pre-winter lawn care consists of aerating the turf—to reduce compaction and make it easier for fertilizer and water to reach the roots—and reinvigorating thin areas with compost and seed. Before you start, get a soil test so that you know the type and amount of amendments to add. (Repeat the test in three to five years.) Then read the steps below to learn how to prepare your lawn for winter.
Just remember: When aerating, fertilizing, or seeding, always go over the turf twice, with criss-crossing paths. You don't want stripes in your revitalized lawn.
Pictured: Roger Cook uses a lightweight rotary spreader to broadcast fertilizer, lime, and grass seed.
Cut the grass down to 1 to 1½ inches, making it easier to aerate and to judge how much compost to add. If your grass is more than 3 inches tall, take it down incrementally over a few mowings—no more than a third of the grass blade at a time—to avoid stressing the plants. This is an important step to prepare your lawn for winter.
Aerating is an essential part of pre-winter lawn care. On a day when the soil is moist, not soggy—the core aerator's hollow tines can't easily penetrate hard, dry ground—take a couple of passes around the lawn's perimeter. This will provide a buffer zone for turning this heavy machine around as you run it back and forth over the rest of the lawn.
Where grass is sparse, prepare for seeding by spreading a half-inch layer of aged compost. I hold a snow-shovelful in the crook of my arm, fling it off with my free hand, as shown, then work it in with a leaf rake. Be sure your compost is cured: dry, crumbly, and cool to the touch. If it's hot and smells, it's more likely to harbor pathogens and burn your lawn.
Distribute fertilizer and pelletized lime (if needed) using a rotary spreader. I use a high-phosphorus fertilizer to stimulate root growth; but you should let the soil test determine the best mix for your conditions. To keep the spreader from dumping too much fertilizer in one spot, open or close the hopper only when the spreader is in motion.
Fill the spreader with seed, set its control to about two-thirds of the bag's recommendation, to account for overlapping passes, and distribute the seed over the compost. As when fertilizing, keep the spreader in motion when opening or closing the hopper. For large areas, you can save time by renting a power overseeder, which slices the turf and drops in the seeds. It eliminates the need to rake in Step 6.
Rake and Water
Mix the seeds into the compost with a leaf rake held tines up, as shown. Water lightly—5 minutes at a time, two to three times a day—until the seeds sprout. Then water once a day for 15 to 30 minutes. Mow the lawn again when the existing grass reaches 3 inches; bag the clippings. After leaves have fallen, cut the grass back to 1½ inches for its long winter's nap.