Spring (March – May)

Mowing - Before green-up, remove dormant grass leaves by mowing to 2 ½ inches with a rotary mower that has a newly sharpened blade. Maintain the lawn at 2 ½ inches, mowing before it gets to 4 inches. Palmetto should be maintained at 2-21/2 inches.  Leave clippings on the lawn.  Mow every 7-10 days in the growing season.  Never cut more than 1/3 of the total length of the blade at any one mowing.  If a mowing is missed and clippings clump on top of the Palmetto, bag or vacuum clippings to reduce matting and shade out.

Fertilizing - Apply ½ pound of nitrogen (N) (enter .5 in the Fertilizer Calculator) per 1,000 square feet in May or 2 weeks after green-up, whichever is last. Use a complete (N-P-K) turf-grade slow release fertilizer with a 3-1-2 or 4-1-2 ratio (12-4-8 or 16-4-8). Yellow appearance may indicate an iron deficiency. Spray iron (ferrous) sulfate (2 ounces in water per 1,000 square feet) or a chelated iron source (like Ironite liquid or granular) to enhance color as needed. Remember that Iron will stain concrete drives and walks so be sure to remove granules prior to watering in.  Submit a soil sample to determine nutrient requirements, if you haven’t already. (Contact your county Cooperative Extension Service for details.) Apply lime if the soil-test report suggests it.

Irrigation - Actively growing St. Augustine requires about 1 inch of water per week, all at once, if possible. If you don’t get enough rain, you will have to water. Sandy soils often require more frequent watering (½ inch every third day). Proper irrigation may prevent or reduce pest and other problems.  Due to the fact that St. Augustine is often planted in shaded areas with restricted air movement it is essential to not overwater this grass.  Reduce irrigation in shaded areas and where heavy soils are present.  St. Augustine suffers from overwatering as this can allow diseases and insects to thrive.

Weed Control - Proper mowing, irrigation and fertilization will reduce weed pressures.  If crabgrass and goosegrass have been a problem, apply preemergent herbicides by the time dogwoods are in full bloom. Control broadleaf weeds as necessary with postemergent herbicides. St. Augustine is sensitive to certain herbicides (2,4-D and MSMA), so always read and follow label directions and use caution.

Insect Control - Control any white grubs if necessary. If drought symptoms or yellow spots occur in a sunny location, check for chinch bug activity. Push a coffee can (with both top and bottom removed) into the ground and fill it with water. Any chinch bugs present will float. Treat for chinch bugs if you have 20 or more chinch bugs per 1,000 square feet.  For any insecticide application read and follow label directions carefully.  Control chinch bugs with Talstar.  Control grubs with Bayer Advanced Lawn® Season Long grub Control Ready-to-Spread Granules annually in the late spring.

Disease Control - During periods of high heat and high humidity combined Palmetto is susceptible to some turf diseases.  It may be a good practice to apply preventative fungicide applications during such periods to maintain healthy Palmetto lawns.  If circular patches of brown grass up to several feet in diameter appear, you may have Brown (Large) Patch. Gray Leaf Spot also may be a problem. Control both diseases as necessary with proper fungicides.  For any fungicide application always read and follow label directions carefully.  
Aerate - Heavy clay soils or heavily trafficked sections of lawn may benefit from aeration. If it is needed, aerate in late spring or early summer when the grass is actively growing and capable of recovery.

Renovation - Replant large bare areas in May (or when daytime temperatures are continually above 60oF) using plugs planted on 12-inch centers or preferably sod!

Summer  (June – August)

Mowing - Palmetto should be maintained at 2-2 1/2 inches.  Maintain a sharp blade and leave clippings on the lawn.  Mow every 7-10 days in the growing season.  If you are mowing more frequently you may need to consider lowering nitrogen applications.  Never cut more than 1/3 of the total length of the blade at any one mowing.  If a mowing is missed and clippings clump on top of the Palmetto, bag or vacuum clippings to reduce matting and shade out.

Irrigation - Same as March through May guidelines. 

Thatch Removal - If thatch was ¾ inches thick last summer, mow grass to 2 ½ inches and use a power rake (vertical mower or dethatcher) with 3-inch blade spacing. A heavy lawn rake can yield the same effect if used aggressively.  Too much thatch is a breeding ground for disease and insects while not enough thatch can allow grass to dry out quickly so try to manage this layer to your advantage.

Fertilizing - Apply 1 pound of nitrogen per 1,000 square feet in June and August and 1/2 pound of nitrogen in July. In the absence of a soil test, use a complete (N-P-K) slow release turf type fertilizer with a 3-1-2 or 4-1-2 ratio. Consult the Fertilizer Calculator to determine the exact amount to apply to your yard. Yellow appearance may indicate an iron deficiency. Spray iron (ferrous) sulfate (2 ounces in water per 1,000 square feet) or a chelated iron source (like Ironite liquid or granular) to enhance color as needed. Remember that Iron will stain concrete drives and walks so be sure to remove granules prior to watering in.  Submit a soil sample to determine nutrient requirements, if you haven’t already. (Contact your county Cooperative Extension Service for details.) Apply lime if the soil-test report suggests it.

Weed Control  - Apply postemergent herbicides to control summer annual and perennial broadleaf weeds. Since St. Augustine is sensitive to certain herbicides (2,4-D and MSMA), always read and follow herbicide label directions carefully and use with caution. Do not apply herbicides unless weeds are actively growing and the lawn is not under drought stress. If crabgrass and goosegrass are present, make a note to apply a preemergent herbicide next spring.

Insect Control - If drought symptoms or yellow spots occur in a sunny location, check for chinch bug activity. Push a coffee can (with both top and bottom removed) into the ground and fill it with water. Any chinch bugs present will float. Treat for chinch bugs if you have 20 or more chinch bugs per 1,000 square feet. Control chinch bugs with Talstar.   For any insecticide application read and follow label directions carefully.  

Fall  (September – November)

Mowing - Same as March through May guidelines.

Fertilization - DO NOT fertilize St. Augustine after August 31. 

Irrigation - Water to prevent drought stress while the grass is actively growing and after the lawn goes dormant to prevent excessive dehydration.

Insect Control - Follow June through August guidelines.

Thatch - Check for thatch layer in early September. If the thatch layer is ¾ inches thick, plan to dethatch in the spring.

Weed Control - If crabgrass and goosegrass are present, plan to apply a preemergent herbicide next spring.

Disease Control  - Check for Brown (Large) Patch and Grey Leaf Spot and treat if present. For any fungicide application always read and follow label directions carefully

Winter   (December – February)

Mowing - Pick up debris (rocks, sticks, leaves, etc.) from lawn. 

Fertilization  - Do not apply fertilizer or lime.

Watering  - Although the lawn will be dormant, water occasionally to prevent excessive dehydration particularly on newly sodded lawns.

Weed Control  - Apply postemergent herbicides to control broadleaf weeds. St. Augustine is sensitive to certain postemergent herbicides like 2,4-D and MSMA, so follow label directions for reducing rates, and use with caution. Selected herbicides like atrazine and simazine can be applied in November or December to control annual bluegrass and several winter annual broadleaf weeds. For any herbicide applications always read and follow label directions carefully.

Disease Control - Check for Brown (Large) Patch and Grey Leaf Spot and treat if present.  In heavily shaded areas St. Augustine will sometimes not go fully dormant.  If this is the case and Brown Patch is present it can do significant damage through the winter months if left unchecked. For any fungicide application always read and follow label directions carefully.
About St.Augustine

This fast growing grass has a medium to dark green color and very coarse leaf texture. With proper maintenance, it provides a dense, lush lawn.  It is a warm-season grass at it’s best in warm, humid areas not exposed to excessive or intense periods of cold weather. 

St. Augustine can only be planted vegetatively. It grows best in fertile, well-drained soils. It has excellent tolerance to shade and good salt, heat, and, to a moderate extent, drought tolerance. It does not tolerate heavy traffic or cold weather.

Since it is fast growing, St. Augustine needs to be mowed frequently. It should never receive more than 4 pounds of nitrogen per 1,000 square feet in a year. With high fertilization rates and irrigation, thatch buildup may be a problem. Thatch can lead to other problems, such as disease and insect damage. Chinch bugs are often a problem, causing leaves to wilt and turn brown. Yellow spots are often associated with chinch bug activity. In addition, Brown (Large) Patch can create brown circular patches up to several feet in diameter that usually warrant treatment.  Grey Leaf Spot is also a common disease affecting St. Augustine.  In the summer months it is recommended to apply preventive fungicides to keep these diseases from occurring as they are very likely to persist. St. Augustine is sensitive to some postemergent herbicides, such as 2,4-D and MSMA; however, some herbicides can be used at lower rates. Read and follow label directions carefully. Following the management practices provided is the best means of preventing and controlling problems in your St. Augustine lawn. Continual loss of grass may mean that you need to select a different turfgrass species, one that is better adapted to your particular yard. Contact Modern Turf for help in identifying and solving turfgrass problems or choosing a more suitable variety for your application.