Growing Turfgrass in Shady areas

Find tips for growing grass in shady areas

Brian Jervis: Ask a Master Gardener   

Saturday, June 25, 2016  

Q: I simply cannot get grass to grow under my oak tree after reseeding it several times. Is there a best grass to use? Dwayne, Tulsa

A: This is a common problem in Tulsa, where we have these wonderful huge shade trees. The shade is good, but growing grass under them is challenging.

Of the turfgrasses commonly grown in our area, tall fescue and Kentucky bluegrass are the most shade tolerant, followed by zoysia, which will tolerate some shade, but still needs a lot of sun. Bermuda and buffalograss must have full sun. Neither will grow in full shade.

When there is not enough sunlight for the grass you wish to grow, there are some steps you may take to improve chances of success. These are outlined in a very helpful OSU fact sheet, “Managing Turfgrass in the Shade in Oklahoma,” available from the Master Gardener website, tulsamastergardeners.org, in the turfgrass section.

If your situation is such that pruning of trees and shrubs could be done for shade management, without harming the plants, this may allow more sunlight and may improve chances of success.

Plus, alterations in how you manage the grass may improve shade tolerance. If you mow the lawn tall in shaded areas (3 inches or more for tall fescue and 2 inches for Bermuda and Zoysia) it will produce more grass blade surface to absorb available sunlight.

Grasses in the shade have improved chances of survival if they receive less fertilizer than the usual amounts recommended. Also, it is better to use more frequent applications of smaller amounts to avoid a surge in growth demand. These grasses also need less water since they take longer to dry out after rain or irrigation. Look to see if the soil is dry before irrigating.

Try to keep the weed competition under control by hand or with herbicides. If using herbicides read the label carefully about the use in shaded areas, some may be more toxic in shade. It is also helpful to remove leaves or other debris that has fallen onto the lawn as soon as possible to prevent blockage of available light.

And if you continue to fail in growing grass in shade after two to three years, it may be time to consider a different strategy to manage your shaded areas. These shady spots can go from being a problem to an asset by planting shade-tolerant ground covers, ornamentals and installing some hardscape (stone element) structures. After establishment the need for maintenance is much less than struggling with turfgrass.

The OSU fact sheet referred to above has a useful section on alternative plantings for areas too shady for lawn grass. Suggestions for annuals are plants such as caladium, impatiens; perennials suggestions include such things as hellebores, hostas, ajuga, Japanese painted ferns and many others. There is also a list of groundcovers, vines and several shade-tolerant shrubs. From this information, you should be able to design and build an attractive shade garden.

6-25-16 Garden Tips

·       Mulch ornamentals, vegetables, and annuals. This reduces soil crusting, cools soil and conserves moisture during hot summer months. Mulch also helps prevent weeds and reduces likelihood of mechanical damage from lawn equipment.  Mulching will reduce about 70 percent of the summer yard maintenance.

·       A disease called “fireblight” is prevalent now. It may infect over a 100 plants in the rose family, but especially apples, crabapples, pears, quince and pyracantha. The bacterial disease is spread by insects and rain and enters the plant through open blossoms. Once infected, the leaves on the involved limb turn brown looking like they have been scorched (hence the name) and that limb dies. The only treatment is to remove the dead limbs. An antibiotic spray can be helpful but only during full bloom and only used to prevent the disease. Some trees are more susceptible than others, consideration should be given to planting disease resistant varieties.