To water, or not to water, that is the question

The state of Alabama is home to warm-season grasses such as zoysia, Bermuda and centipede. These grasses require specific care to keep your yard looking its best. 

Dave Han, an associate professor in Auburn’s College of Agriculture and a specialist with the Alabama Cooperative Extension System, has a lot of experience in caring for grass, whether it’s grown on golf courses and football fields, in Auburn’s research facilities or in his own backyard. 

Han’s expert advice? Water early and water well, don’t be afraid of drought and always fertilize in summer.  

Measure once, water twice 

When it comes to watering your lawn, the frequency and duration depends on the species of grass, soil drainage and how much water an irrigation system puts out. But generally, Han suggests watering twice a week for 15-20 minutes in the early morning, before the sun comes up, to avoid losing water to evaporation as the day heats up. 

To ensure you’re giving your lawn the proper amount of water on those mornings, Han recommends measuring how much water your irrigation system actually puts out.  

“Every system is different,” Han said. “You can determine your irrigation system’s output by setting out many rain gauges or other receptacles and measuring how much water they catch when you run the system for a given time.”  

It’s okay not to water 

Southern grasses can survive long droughts by going dormant. Han said that Bermuda, zoysia, centipede and St. Augustine grass can all survive up to 90 days without rain or irrigation while dormant, as long as they are healthy going into the drought. 

“If you don’t mind a brown lawn, it is okay to let them go dormant,” he said. “During dry spells, watering once a week should keep the grass green, even if it’s not growing very fast. And avoid using herbicides during droughts or when the grass is stressed by other factors.” 

Fertilize now! 

Now is the time to fertilize, and Han recommends specific fertilizing rules based on the species of grass.  

• Bermuda: Fertilize once a month between now and September with one pound of nitrogen per 1,000 square feet of grass.  

• St. Augustine: Fertilize four times a season, or every six weeks.  

• Zoysia: Fertilize only once or twice a year. 

• Centipede: Once a year is enough. 

Mow, mow, mow your lawn 

Han recommends mowing your lawn at a height of 1½-2 inches, although St. Augustine can be cut a little higher, at 3-4 inches, and tall fescue should also be cut around 3 inches tall.  

“You should mow at least once per week, but for faster-growing grasses like Bermuda, twice a week would be better,” he said.