How Cooler Temperatures Are Affecting Lawn and Landscape

Is It Spring Yet?

As is the case with most years, sometimes it will warm up early, fooling a lot of plants, including turfgrasses, to start the annual spring green-up. Only to be broadsided with an arctic blast and cooler temperatures that pushes plants back into winter dormancy.

Cool-season turfgrasses like bluegrass, ryegrass and the fescues are somewhat accustomed to these weather fluctuations, but the warm-season grasses, such as Centipede, St. Augustine and Bermuda grasses can be greatly affected by a cold snap after they have been coaxed into an early spring green-up by an early warm up. Such is the case with many lawns in the warmer parts of the United States.

Roland Freund, Franchise Owner in the Houston, Texas area, posted some information on his Facebook page about lawns in his area that are turning a purplish color due to some cooler temperatures that have pushed southward. Turf turning a purple color is often a sign of stress and when warm season grasses that have started to come out of winter dormancy get hit with freezing temperatures, the result can cause turf to turn an off-color. Luckily, it is a temporary condition and the turf generally recovers on its own.

Some warm-season grasses that have started to green-up can display an usual camouflage-like pattern when subjected to cooler to freezing temperatures, such as what you see in the picture below. This can happen to Bermuda and Zoysia grasses. Just as is the case with St. Augustine, this is a temporary problem and the grasses usually grow starting growing and the damage disappears as new grass blades cover up the blades that have turned brown.

grass in cooler temperatures
The one unknown for warm-season turfgrass lawns is how the extremely cold temperatures that affected much of the South in early to mid-January. Temperatures in the single digits is a common occurrence in the areas where cool-season turfgrasses grow, but this year many parts of the south experienced near record setting cold weather for an extended period. It is still a little early to tell if those temperatures had a lasting effect on lawns and landscapes in the South. I will tell you that I was conducting a training session in Lake Charles, Louisiana towards the end of January, and I saw many palms trees whose fronds were badly damaged by the cold weather. It is going to take some time for those trees and the lawns to recover from the cooler temperatures.

Caring for warm-season turfgrass lawns at this time of year focuses on controlling existing winter weeds and preventing the growth of annual grasses like crabgrass and goosegrass. Weeds are much more durable than turfgrasses and will quickly come back from the onslaught of freezing temperatures. It is almost time to start fertilizing these grasses, but patience is necessary. Applying fertilizer too early can have detrimental to these grasses.

As the South gets ready for the beginning of spring, what about the lawns and landscapes in the cool-season areas? Spring applications have started for lawns in the Transition Zone where Tall Fescue is the predominate turfgrass. Except for parts of Northern California, Oregon and Washington, it is still too early to prepare for the first application of spring.

It is a best practice to wait until the ground is no longer frozen to apply the first application. In many northern states, this is mandated by law to prevent run-off from fertilizer or weed control products off of the frozen ground. It is still early and spring will be here before we know it, unless, of course, the area is hit with a late winter storm – not an uncommon occurrence in March or even early April. The best thing to do is make sure the lawn mower is tuned up and plan ahead for the season. Spring is just around the corner, so remember you can count on your local Spring-Green to make sure your lawn looks green, and thick for the upcoming season!