Mowing. Fertilization. Irrigation: What you need to know about lawn care

Here's what you need to know before you mow.

EUGENE, Ore. - Keeping a lawn green through the dry summer months can be a challenge for many homeowners. Particularly in the Willamette Valley where the most common grass is unique compared to other parts of the United States.

"When we compare the Willamette Valley of Oregon to other areas of the country, probably the biggest difference is the dominate grass in home lawn is perennial ryegrass," says Alec Kowalewski, assistant professor and turf specialist with Oregon State University. Kowalewski conducts research with OSU's Extension Service with the goal of creating best-practice methods to take care of turf and treat it for common fungi and weeds.

"Perennial ryegrass is great in the valley because it remains green through the winter. But it does require more fertilization and consistent irrigation," says Kowalewski. "For general lawn care, the three primary cultural practices are mowing fertilization and irrigation. You should be putting more time and money into these three cultural practices when maintaining a lawn."

In short, mow the lawn, fertilize it and water it. But it's a touch more complicated than that.

Mowing is exceedingly important especially when it comes to length. Ideally each lawn should be between 2 to 3 inches long. "A common mistake I see homeowners make is typically people want to mow their lawn a little shorter than they need," says Kowalewski. "They go to the golf course or an athletic field and they think their lawn should look the same. Really it shouldn't it's not the same grass."

The clippings from mowing can also be beneficial to the lawn as they return nitrogen and other nutrients to the grass. Though when not bagging, be sure to never cut more than a third of the grass as once, doing so could be detrimental to a lawn. Otherwise, bagging lawn clippings is purely about athletics and personal preference.

Fertilizing the lawn is important as well. Without it the grass will struggle to find the chemicals needed to promote growth. Kowalewski says one of the best types of fertilizer for lawns in the state has the numbers 25-3-10 printed somewhere on the front. "Which is 25% nitrogen, 3% phosphorous and 10% potassium and that would be a great fertilizer for the typical home lawn."

The trick with fertilizer is not using too much or too little. Usually four times a year is all a lawn needs to grow and stay healthy. A successful schedule is to fertilize on the holidays.

"Fertilize on Memorial Day, July 4th, Labor Day and Halloween or thanksgiving depending on your climate," recommends Kowalewski. Those who see snow sooner than Thanksgiving, such as Eastern Oregon and those in the Cascades, are better off laying down fertilizer around Halloween. Others who rarely get snow until late December or early January, such as the Willamette Valley can get away with fertilizing around Thanksgiving.

The final task when maintaining a lawn is an appropriate watering schedule. For this Kowalewski says watering small mounts frequently is better than large amounts infrequently. "Run your irrigation three times a week at a quarter of an inch each time," he says.

A neat tip here: take an empty tuna can and set it out on the lawn with the sprinklers going. Once it fills to the brim turn off the water. Kowalewski says Perennial ryegrass should see about 0.75" of water a week. As a result, if a lawn receives rain, that water can be deducted from the amount of water added to it through irrigating.

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