Turf Tips

What to do about deteriorated lawns

This year there were multiple causes for turf decline in home lawns. High temperatures and drought were the primary causes for a decline in turf and an increase in weed incidence. During warm weather (especially temperatures > 87 °F) cool-season grasses like Kentucky bluegrass have trouble making energy while much energy is needed to maintain plant functions. In short, cool-season grasses don’t make energy well when it is hot out and as a result they don’t grow (roots or shoots) well in hot weather which can lead to a decline in turf quality. Water is also critical to the growth of turf. Water is a key part of photosynthesis and respiration reactions as well as many other plant metabolic activities. Turfgrass leaves and shoots are comprised of about 80% water. The recent lack of rainfall in parts of Indiana has led to a decrease in growth or summer dormancy (drought).

Some grasses such as Kentucky bluegrass enter a summer dormancy when soils begin to dry. Summer dormancy is a process where the plant stops growth and turns brown (dormant) but it is not dead. When rainfall returns following drought, Kentucky bluegrass will emerge from summer dormancy and resume normal growth. Even if drought tolerant species are utilized, turfgrasses can experience drought injury in the summer, especially where irrigation is not available, on southern slopes, and on shallow or compacted soils.

Drought Facts

Many homeowners in central and southern Indiana are trying to figure out how best to cope with the current drought because it is affecting their normal 1) fall seeding, 2) fertilization, 3) and weed control. Below are some strategies on how to cope with the current situation.  The maps below show illustrate the lack of rainfall in central and southern Indiana over the past 90 days (since the heavy spring rains).

Managing turf during drought

Should I fertilize right now?

Should I apply a herbicide right now?

Should I seed right now?

For more information about recovering your lawn from drought see the following publications
Rejuvenating Drought Areas after the Drought of 2002
Lawn Improvement Programs

Aaron Patton, Turfgrass Extension Specialist

Send corrections, suggestions, and comments to biehlj@purdue.edu