Ask The County Agent: Shade is major challenge for turfgrass

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By STEPHANIE BUTCHER, Coordinator, UGA Extension Coweta County 

Question: What’s wrong with my turfgrass?

Agent: Too much shade is one of the most common problems I see when homeowners are unhappy with their turfgrass. Although shade is a wonderful benefit of trees, it is a major challenge for growing turfgrass. 

Basic management practices for growing grass in shaded conditions consist of proper turfgrass selection, cultural practices, pest management, environmental modification, and traffic control. Keep in mind that if you are trying to grow turfgrass in an area that gets less than 4 hours of sunlight a day, then you may want to consider something other than turfgrass for that area. No turfgrasses grow in heavy shade. 

Lack of sufficient sunlight causes a reduction in photosynthesis. As a result, lawn grasses do not handle heat, cold, disease, drought and foot traffic as well. In addition, competition for nutrients from trees and shrubs negatively affects turfgrass growth. Disease problems can also be more severe in shade due to higher humidity, reduced air circulation, and prolonged dew retention. As a result of these factors, turfgrass grown in the shade will be thin compared to that grown in full sun. 

Turfgrass Selection

Certain turfgrasses perform better in shade than others. Of the cool-season grasses, tall fescue is a common choice in Georgia. For warm-season grasses, St. Augustine is by far the most shade tolerant but is more susceptible to damage from chinch bugs and can often be damaged by cold during an exceptionally harsh winter. ‘El Toro’ zoysiagrass is shade tolerant. Bermudagrass is the least shade tolerant of any turfgrass, but one of the newest cultivars, TifTuf ™ does surprisingly well. You would still need at least 5 ½ hours of sunlight though. 

Cultural Management

  • Raise the mowing height to the highest recommended height. This increased leaf area helps the plant capture more sunlight and thus manufacture more “plant food”.
  • Nitrogen needs for turfgrasses are generally 50% lower in shaded environments than recommended for full sun. This generally means no more than one to two pounds of nitrogen per 1000 sq. ft. per year. Since most turfgrasses and trees require the same amounts of fertilizer, soil testing should be used to determine lime and fertilizer needs. Surface applications of fertilizer are generally preferred, but it should never be placed directly on exposed tree roots. This includes fertilizer plus herbicide products (commonly called weed-and-feed).
  • Irrigate deeply and infrequently to encourage deeper rooting and to reduce the humidity and time the grass leaves are moist. Early morning is the best time. 
  • Remove tree leaves, grass clippings, and any other debris that might prevent light penetration or encourage disease activity.
  • Follow a good pest management program to reduce competition from weeds, and injury from diseases and insects. 
  • Control traffic to reduce wear injury. The added stress of traffic can easily cause the loss of grass in shaded areas.

Environmental Management

Ornamentals that have dense canopies and shallow roots normally make turfgrass survival difficult even if proper management practices are used. When possible, select trees and shrubs that are deep-rooted and have relatively open canopies. 

Some measures can be taken to aid grass survival, whether desirable or undesirable ornamentals are present. Selectively prune branches, particularly low branches, to aid in air movement and light penetration. Ideally, the lowest branches of trees should be more than 8 feet above the soil surface. Remove any unnecessary trees and shrubs. Use recommended species and sufficient spacing between plants when placing new plants.

If quality grass cannot be maintained, then consider landscaping with ornamentals and shrubs, or planting an appropriate shade-tolerant groundcover such as mondo grass, creeping Charlie, ajuga, or pachysandra. 

For more information on landscaping in shaded environments, contact the Coweta County Extension office at 770-254-2620 or email [email protected]

The University of Georgia College of Agricultural & Environmental Sciences is an equal opportunity, affirmative action organization.

Photo Credit: Dan Gill, LSU Ag Center

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