What is Dormancy?

We get it - dormant grass isn’t the prettiest to look at. But did you know that dormancy is a self-imposed protection measure for your grass? That golden grass is your lawn’s way of avoiding burnout from stressful conditions.

Why Does Grass Go Dormant?

There are two main causes of dormancy: 

  1. Temperatures that are consistently above or below optimal growing conditions.
  2. Prolonged dry periods resulting from lack of rainfall or poorly functioning irrigation systems. 

Cool season grasses will start to slow down once temperatures drop below 56F consistently and will also enter a “summer dormancy” period if drought stressed.

Warm season grass growth will slow down when temps get below 74F and tend to go dormant in the winter when temperatures consistently remain under 60F. Don’t worry – things will start to green up again in the spring when soils warm up and nighttime temps hit 60F.

Sunday Dormancy Pro Tips

#1 How do you know if you have warm or cool season grass? If your lawn turns brown after a frost then chances are, it’s a warm season grass. If it stays green after a hard freeze then you likely have a cool season species.

#2 Keep in mind: many factors including fertilization, irrigation, and specific grass type, drought and other weather conditions will impact when the lawn enters and emerges from dormancy.

#3 Has your grass gone dormant for the winter? Now is the perfect time to dormant seed your lawn!

By the way, Sunday applications are timed to avoid dormant periods! When your grass is dormant, you should not apply fertilizer, which can lead to overuse of energy reserves, or mow, which can further stress the plants. 

What happens when grass goes dormant?

Dormant, brown grass may resemble dead grass, but the biggest difference is at the soil line, where the grass “crown” is. The crown of the plant houses the next generation of leaves and roots. As grass is stressed, metabolism slows and leaves get sacrificed in order to conserve energy. The crown needs to stay hydrated to survive and sustain the little leaf buds that grow to replace those dormant leaves.

Root survival is also critical. Soil temps are much slower to respond to climate conditions than air temperature – which is a good thing for your grass! It means your grass roots are insulated and can better withstand temperature fluctuations. So even if the leaves turn brown, the plant is still living. Roots not only anchor new top growth when conditions become favorable, but also supply energy to kickstart growth as new leaves emerge. Eventually, when the new leaves are big enough, they will take over and serve as solar panels for energy production.
Remember – dormancy is your lawn’s way of keeping itself healthy. The grass will bounce back when it’s ready!

Sources

J.C. Stier, B.P. Horgan, and S.A. Bonos (eds.). Turfgrass: Biology, Use, and Management

 

Duble, R.L. Spring Transition in Bermudagrass

Baldwin, C.M., H. Liu, L.B. McCarty, H. Luo, and J.E. Toler. Dormant bermudagrass spring green-up influenced by shade.