Lawn renovation involves restoring a deteriorated turf grass area to an improved condition.

Depending on the condition of the turf, this process can be accomplished without establishing a new lawn.

Lawn renovation is time-consuming and moderately expensive and should not be performed unless steps are taken to correct the underlying cause of turf deterioration.

The first step in lawn renovation is to correct the primary cause of turf deterioration.

Such things as drought, excessive shade, tree root competition, poor drainage, soil compaction, inadequate fertility, acid soils, weed or insect infestation, disease, thatch build-up, improper mowing, poorly adapted grass species and cultivars, and others may contribute to poor turf.

Most of these problems can be corrected by renovation, proper turf grass selection, and improved maintenance practices.

Shade problems: Shade problems may require removal of some trees, pruning and planting turf grass species that are adapted to shaded conditions. Tree roots may need pruning to reduce competition with grasses for water, air, and nutrients.

Poor drainage: Drainage problems can often be corrected by breaking up compacted soil or through installation of drainage tile. Where surface drainage is insufficient, the site may have to be regraded so that water is removed from the site.

Soil fertility and acidity: Inadequate fertility or acid soils (which can limit turf growth) can be determined by testing the soil. Soil testing mailing kits are available through your local county Extension Office at a cost of $10. The results will include recommendations for the amounts of fertilizer and lime that need to be applied to the lawn.

Pests: Pests that cause serious turf damage need to be identified and controlled.

Thatch: Thatch is a tightly intermingled layer of partially decomposed grass stems and roots that develops beneath the actively growing green vegetation and above the soil surface.

Thatch decreases the vigor of turf grasses by restricting the movement of water, fertilizers, and pesticides into the soil. Turf grass roots also grow into the thatch and may become desiccated as the thatch dries.

Thatch builds up over a period of years and must be periodically removed by mechanical means. Thatch removal equipment can usually be rented from garden centers or rental outlets.

Mowing: Mowing on most lawns should be at least 2-1/2 inches or above and on a regular basis as long as the grass is growing.

How frequently the grass is mowed depends on the growth rate of the grass. No more than one-third of the total leaf surface should be removed at a given mowing.

Clippings do not need to be removed provided the lawn is mowed on a regular basis. All mowing equipment needs to be sharpened and adjusted periodically.

Species and management: Species not adapted and improper management are perhaps the most common cause of turf grass deterioration.

Species and management must be adapted to the conditions present at the site. Other problems include the use of inferior turf grass cultivars and poor-quality seed.

Once the reasons for lawn deterioration are recognized and steps are taken to correct the problems, the renovation program can begin.

The Great Allentown Fair: The Fair runs Aug. 28 through Sept. 2. The Penn State Master Gardeners will have a booth in the Agri-Plex where you can ask all your gardening questions.

It is also a great time to check out all the fruits, vegetables, flowers, Christmas trees, nuts, and so many other items on display in the Agri-Plex. You might see something different that you want to grow next year.

“Growing Green” is contributed by Diane Dorn, Lehigh County Extension Office Staff, and Master Gardeners. Information: Lehigh County Extension Office, 610-391-9840; Northampton County Extension Office, 610-813-6613