How To Successfully Care For Your Cool-Season Grass

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If you live in the northern half to two-thirds of the United States, odds are you have a strain of cool-season grass in your yard. Kentucky bluegrass, perennial ryegrass and tall fescue are just a few of the most popular types of cool-season grass. While these grasses have been adapted so that they can grow and thrive in a wide swath of the country and areas with wide-ranging temperatures, they also need to be cared for properly. This means proper watering, fertilizing, and mowing techniques need to be employed in order to ensure your cool-season grass can survive and thrive throughout the year. 

For starters, as the name implies, cool-season grass is best suited for milder climates. As the weather turns warmer and drier, a variety of issues can arise. With exception of some strains of fescue, the drought tolerance of cool-season grasses ranges from low to medium. So, proper watering techniques are a priority. However, you may want to think twice about watering every day. While most of these grasses require about 1.5 inches per week, it is best to deliver that in a couple of thorough doses as opposed to light waterings on a daily basis. This will encourage deeper, more resilient root structure to form, enhancing the grass' ability to gather nutrients and deal with dry conditions.

How and when you mow your lawn also makes a difference. Most cool-season grasses do best when allowed to grow relatively tall, between 2.5 and 4 inches. Unfortunately, this doesn't necessarily mean mowing less often. Rather than just letting it grow wild, continue to mow frequently, but follow the one-third rule, never cutting more than a third of the grass' length in a single mowing session. It is also important to utilize sharp blades, which will minimize the stress on your lawn. So, if you see signs you need to sharpen your mower blades, do so immediately. 

The mild weather seasons of spring and fall are the best time to fertilize your cool-season grass and aerate your yard. Before adding fertilizer, however, it is important to test the soil with a Garden Tutor Soil pH Test Kit or similar product. Your aim should be to keep your soil pH between 6.0 and 7.0 for cool-season grasses. Spring is also a great time for overseeding your lawn and applying pre-emergent herbicides to prevent weeds from popping up. If you notice signs of any lawn pests such as grubs or chinch bugs, your best bet is to encourage natural predators such as birds to handle the problem, although some insecticides are safe for cool-season lawns if applied during mild temperature periods.