Spring Green Up Problems in Warm Season Turf Grasses
When the days of winter seem to come to a slow close, we all look forward to the warmer days of spring. We think of the birds chirping, fragrant flowers blooming and everything in transition to become lush and green. However, one of the most common asked questions is “It’s spring so why isn’t my turf greening up?” There are a few common problems regarding warm season turf grasses and the greening up process.
This is one of the most common problems with turf grass green up. All types of turf react differently to mowing heights. For example, St. Augustine turf cannot tolerate being scalped like Bermuda, without damage occurring. Regardless of the type of turf speices severe scalping or mowing at improper heights will contribute to the delayed greening up of turf. In a single mowing no more than one-third of the leaf blade should be removed. In most cases, if more than one-third is taken, the turf will show signs of stress. Proper mowing heights should be followed according to the type of turf you have.
- Bermuda – 1 to 1 ½ inches
- Centipede – 1 ½ to 2 inches
- St. Augustine – 2 ½ to 3 inches
- Zoysia – 1 to 1 ½ inches
Fertilizing too early in the season will accelerate the green-up but can also have negative effets on your grass. Applying fertilizer before soils are warm enough to support continual growth, no matter the type of grass, can cause stress on the turf. A good rule of thumb for applying the first fertilizer of the year is apply when your turf is actively growing and turning green (usually after April 1st) . DO NOT RUSH IT! If your turf is taking it’s time starting to grow then you should be patient and wait.
As turf ages, thatch can become a problem resulting in delayed green-up. One of the major causes of thatch build up is mowing outside of the recommended height for your type of grass. Thatch build up slows the ability of nutrient take in which will result in delayed green-up in spring. The build-up of the thatch layer also makes the turf more susceptible to diseases.
Diseases can appear during the green-up. Excessive quick release nitrogen applications will quickly promote fungal problems, one imparticular, Rhizoctonia. Rhizoctonia, also called brown patch, is the most common and appears in large yellowing circles. This turf disease can be controlled by applying fungicides or by being manually removed.
There are many issues that will affect how fast turf grasses will green-up in the spring. Some issues are in our control while others are not. The best thing we can do for warm turf grasses are to manage and control what we can and leave the rest up to mother nature.