DALLAS Tis the season for planting, fertilizing and watering lawns to get them as lush and green as possible, said Dr. Jim McAfee, an Extension turfgrass specialist.
But for many homeowners this year, all the fertilizer and watering in the world won’t be enough to keep their St. Augustine and centipede grass lawns from yellowing and thinning, McAfee said.
Unlike previous years, such diseases as take-all root rot, brown patch and grey leaf spot are not the main problem, McAfee said. Instead, homeowners are now experiencing fallout from the prolonged drought. McAfee said 2005 was one of the driest years on record and North Texas is 20 inches behind on rainfall. There is no water in the soil, he said, and lawns are stressed.
“What we’re seeing this year is desiccation or root damage due to the drought and people not watering enough,” McAfee said. “It’s been nine degrees warmer than average for the year. Even though people may have been watering some, with these dry conditions and the winds, it just takes more water.
The high winds and freezes we had in December and March were an added problem. Yards under dry conditions when those freezes occurred were hit the hardest.”
A secondary problem caused by drought is that lawns already stressed by environmental conditions are also highly susceptible to such diseases as take-all root rot, McAfee said.
Take-all root rot is a fungi which attacks the plant’s root system in the fall and the spring when soil temperatures are in the 60 to 65 degree Farenheit range.
He said the old advice of applying manure is no longer recommended, because some manures can be alkaline and salty. So what’s a homeowner to do? The answer is spaghum peat moss.
“It’s an organic product and you can get it anywhere,” McAfee said. “Topdress the affected areas of the lawn with two bales of peat moss per 1,000 square feet.
“The theory is that spaghum is an acidic material and holds acidity in the soil, which in alkaline soil helps control the growth of the plant,” McAfee said. “That is under research right now in six states thanks to a grant from the Environmental Protection Agency.”
McAfee said it is still too early to determine how much of the grass will recover.
“People need to have patience,” he said. “Don’t try to force it by putting out a lot of water and fertilizer, because that could make matters worse. It tries to force too much top growth when the plant doesn’t have a root system to support that growth, which means it puts an additional stress on the plant.”
McAfee said homeowners should put 1 inch of water per week on their lawn and mow it at least once each week. For St. Augustine lawns, mow to a height of 2 to 2 ½ inches in sun and 3 to 3 ½ inches in shade. For centipede lawns, mow to a height of 1 to 2 inches each week.
McAfee said he is hearing landscapers and lawn care companies are being inundated with questions from homeowners because their yards are looking bad.
“I don’t want to send the message for everyone to get out there and turn on their sprinklers and run them everyday,” McAfee said. “The lakes are dry and it is not necessary. Overwatering is problematic too. We’re stressing proper watering and conserving water for the dry summer months.”
McAfee said most of North Texas is under stage two water restrictions, but many cities are already expecting to go to stage three by June. He said details of the water restriction levels vary slightly from city to city but generally stage one is normal water use following proper watering guidelines; stage two is voluntary water restriction; stage three restricts watering to once per week between the hours of 10 p.m. 6 a.m., and stage four prohibits outside water use for landscapes, washing cars and filling pools.