Tips on managing turf in the shade
Turfgrasses can be difficult to grow in shady areas and proper management strategies are needed for success. The following is a list of tips for growing turfgrass in the shade in Oklahoma.
•1. Right plant, right place.
Select the most shade tolerant species or cultivar available according to site usage.
•2. Remove or selectively prune trees and shrubs if feasible.
The north side of buildings, homes and other non-moveable structures may not be conducive to turfgrass growth. Perform a sunlight site assessment by estimating the daily length of full sunlight over the area during the growing season. If the average is at least eight hours of sunlight, bermudagrass may work. If at least six hours, zoysiagrass may work. If less than six hours, then tall fescue or alternative landscape planting materials may be the best option
•3. Increase the mowing height to at least 3 inches for tall fescue (or other cool-season grasses) and at least 2 inches for bermudagrass or zoysia.
In addition, it is likely that these areas can be mowed less frequently than fullsun areas. This would also help to reduce traffic stress to the area. If you are managing warm-season grass in the full sun and cool-season grass in shade, mowing equipment should be adjusted based upon recommended heights-of-cut by species for shady versus sunny areas.
•4. Fertilize lightly and frequently as opposed to heavy and infrequent.
Shaded turfgrass areas can survive with half of the nitrogen needed to maintain turfgrass in the full sun. In the shade, bermudagrass may need no more than 3 pounds of nitrogen per 1,000 square feet per year. Zoysia or tall fescue may need no more than 2 to 3 pounds of nitrogen per 1,000 square feet per year. If possible, apply fertilizer at the rate of 0.5 pounds of nitrogen per 1,000 square feet per application, making three or four applications over the season. For warm-season grasses, only fertilize during the warm summer months.
For cool-season grasses, only fertilize during the spring and fall. If possible, use blended fertilizers containing both a quickly available and a slow-release nitrogen fertilizer source to avoid a quick flush of growth. Always apply fertilizers based on soil test results.
•5. Avoid excessive foot and equipment traffic.
Instead of mowing shady areas every time you mow full-sun areas, mow every other time. Try not to use heavy lawnmowers or tractors in shady areas or at least try not to mow or drive over the same tire tracks every time.
•6. Reduce irrigation amount and frequency when compared to fullsun areas.
Shade areas take longer to dry out than full-sun areas. If shady areas are constantly wet, there is a significant increase in the probability of disease development, especially for cool-season grasses such as tall fescue. Allow the area to sufficiently dry between watering. If you have an automatic irrigation system, put shady turf areas on a separate zone from fullsun areas. Turfgrasses in the shade that are directly competing with large trees may need more frequent watering than turfgrasses under building or structural shade.
•7. Remove weeds either by hand or with herbicides.
In a home lawn situation, it may be feasible to remove weeds in shady areas by hand rather than using herbicides. Herbicides can often have a phytotoxic effect on desirable turfgrass plants. Herbicide phytotoxicity to desirable turf plants may be exacerbated by shady conditions.
•8. Remove debris and leaves, especially in the fall and spring.
Tree leaves and other debris only serve to block precious light to the turfgrass plant. Raking and removal is necessary and can often make a nice compost/mulch pile for other landscape beds.
•9. Overseed, reseed or sod?
For warm-season grasses, complete this task in the late spring/early summer. If using zoysia in a shaded site, it will usually need to be installed as sod since development from seed will be extremely slow. For best results with cool-season grasses, seed or sod in the fall.
•10. Be prepared with other planting options if necessary.
If you have tried to use tall fescue and/ or Kentucky bluegrass combinations and they have repeatedly failed in the shade over a 3-year period even after selective tree pruning and modified management for shade, it is time to move to an alternative shaded landscape strategy that can include shade tolerant ground covers, ornamentals and hardscape elements.