As heat hits the upper 90’s in Maryland, keeping your lawn healthy can be a challenge. There are several things you can do to help promote a healthy lawn.
- Mow High
If you have ever seen burnt grass or unhealthy lawns, one of the causes is mowing too low. There is a direct relationship between the length of grass and its roots. The longer the grass, the longer the roots. Longer roots reach further down into the soil for more moisture and key nutrients. Set your mower so the grass is a minimum height of 3” during the summer.
During times of drought with little rainfall it is critical to water your lawn (assuming there aren’t any local watering restrictions). Grass needs at least 1 1/2” of water a week, especially during summer. To find out how many inches of water your sprinkler uses, set up open containers around your yard. Run the sprinklers for 20 minutes, then measure the depth of water in each can. Multiply the average depth by three to find the inches per hour. It is better to water using longer soakings than short soakings. Water as early in the day as possible or in the evening. Watering in the middle of the day can be wasteful as water evaporates quicker. Do not water close to nightfall as this will encourage fungal development. If you see runoff of water, turn the sprinkler off the allow the lawn to absorb the water then turn it back on again.
Meanwhile, fertilizers leave salt in the soil, and if you do not flush the lawn with fresh water on a regular basis, those salts build up in the soil. Other times, water sources have traces of salt in them; this is especially true of urban or arid areas. An excess of salt in the soil can cause root burn or make it difficult for your lawn's roots to absorb water.
Aerating involves perforating soil at even intervals to alleviate compaction, allowing water, air, and nutrients to penetrate deep into the surface. You can use a garden fork on smaller lawns. You might find it easier to use a machine on larger lawns. Doing this will also help with water runoff when watering.
All plants eventually deplete the nutrients in the soil and a lawn more so than others as it’s the one plant we tend to cut consistently, taking with it each blade's personal store of nutrients. Within 6-8 weeks of feeding, microbes in the soil have processed most of the nutrients for your lawn to absorb. You need to replenish these nutrients with another feeding. A well-fed lawn grows in thick, crowding out weeds and cooling the soil, which helps it handle the heat.
This is probably the easiest of them all. Almost without exception, lawn clippings should always be mulched back into the lawn. The benefits of mulching lawn clippings are too numerous and valuable to ignore. From providing nutrients for the soil to saving significant amounts of time and money, mulching the lawn clippings just makes sense. Mulching is best accomplished with a mulching mower, which is just like any other mower with a few modifications. Mulching kits are usually an option available to mowers at the time of purchase, but any mower can easily be retrofitted, as well. Special "mulching" blades with extra cutting surfaces are used in conjunction with added baffling underneath the mower. The output or chute is blocked to trap the clippings underneath the deck. The baffling helps move the clippings around within the mowing chamber and allows them to be cut multiple times and blown down into the surface of the lawn.