If you're thinking of aerating your lawn, here's some information that might come in handy. Aeration must be done at a specific time of year, depending on the type of soil and grass you have. There are two different types of lawn grass - cool season and warm season.
Cool season turf wakes up from its summer dormancy at the beginning of Autumn, and will grow robustly while temperatures are lower and there is reduced weed competition. Because your lawn is growing vigorously at this time, it will recover more quickly from the stress involved with aeration. The trick to Autumn aeration is this: Allow your lawn a growing period of approximately 4 weeks prior to frost. Cool season grass types that should be aerated in the Fall include Fescue (red, tall, hard, or chewings), Kentucky bluegrass, Ryegrass (both perennial and annual), Rough bluegrass, and Creeping bent grass.
Warm season turf start their active growth period in the Summertime. It is best to aerate your warm season lawn during the period between late Spring and early Summer, when its growth will rapidly fill in any holes that are created. Warm season grass types that should be aerated during late Spring and early summer are Bermuda Grass, Centipede grass, Bahia grass, Buffalo grass, Zoysia grass, and St Augustine grass.
Remember that different kinds of soil may need more frequent aeration. If you have an arid climate, you'll want to aerate two times a year to enhance the health and growth of your turf. A sandy lawn should be aerated only one time each year, and possibly only once every two years. If you have clay soil that compacts easily, then you'll need to aerate at least once yearly.
Here's a few tips to help you with aeration:
- If your lawn is newly planted, wait at least one year to aerate, so that the grass will be well established
- Control any weeds before aerating, since the aeration process is likely to spread both weed seeds as well as parts of weedy roots
- Aerate just before reseeding or fertilizing your lawn since aeration will create openings for seeds and nutrients to penetrate the soil
- You should aerate while your soil is still moist (not saturated though!) - If your soil is too wet it's likely to clog the tines of your lawn aerator so it won't penetrate deeply. The best moisture balance, prior to aeration, is absorption of about one inch of water, either via irrigation or rainfall. Translate that into watering for an hour one day before aeration or, if you have hard soil, for shorter periods of time for several days before aeration
- Above all, do not aerate during high heat or drought time periods - Your lawn will become stressed if heat is allowed to penetrate too dry soil
Now on to the topic of over-seeding. Kids, pets, and the weather can all be very tough on lawns. If you apply some grass seed on top of your existing lawn, it will help to reinvigorate the lawn as well as fill in any bare spots. Overseeding is also an easy and efficient way to thicken and strengthen your grass, plus helping it to protect itself naturally against problems with weeds.
When should you overseed? Southern lawns should be overseeded during late Spring all the way to mid-Summer. That's the ideal time for overseeding warm season grasses. Northern lawns can be overseeded either in Spring or in Autumn. During Fall the air is cooler, but your soil still is warm, and that combination is perfect for your cool season grass seed.
Here's a few tips on how to overseed your lawn:
- Prep is important - Mow your lawn first at the mower's lowest setting. Bag all the clippings. Now the seed will be facilitated by having direct contact with your soil when it's spread. Make sure to rake after mowing to remove dead grass and debris, and to loosen the soil
- Time to seed - Just fill up the spreader with the chosen grass seed, make sure your setting is adjusted in accordance with the label directions, and seed
- Water the lawn one or two times a day, whatever is right for your weather conditions, up till your brand new seedlings have attained the same height as your existing lawn