17 Sep Fall Maintenance Tips for Your St. Augustine Lawn
Fall Maintenance Tips for Your St. Augustine Lawn
With the changing of the seasons also comes the changing of temperatures, weather and soil conditions. It’s important that you change your St. Augustine maintenance around during the different seasons because the grass and environment will have different demands. This Sod U article compiles a list of generic tips to help your St. Augustine transition into the colder months ahead. Be sure to also check out our Homeowner Maintenance Guides for generic St. Augustine, Palmetto® St. Augustine and CitraBlueTM St. Augustine. If you’re looking for maintenance tips on a different type of grass, take a look at our Fall Lawn Maintenance Tips article.
Fall Mowing for St. Augustine
When it comes to mowing your St. Augustine, a typical height, depending on the variety is about 2–4 inches. However, during the fall, you should maintain a height that’s slightly higher than that of the summer. This encourages deeper root growth so that your grass survives during winter dormancy. The roots are what keeps the grass alive underground while the blades above ground endure harsh temperatures. For more information on mowing heights, visit our Lawn Mowing Guide.
Fall Watering for St. Augustine
In the fall, you will want to water the St. Augustine less as temperatures begin to drop. If you water your grass too much, it could lead to disease during this time. Your St. Augustine generally only needs about one inch of water weekly including rainfall. You will actually want to water a little less than this during the fall months, though. Fall is one of the most opportune times of the year for fungus to start appearing. This becomes even more likely if you are overwatering your grass or have fall leaves on the ground that create areas of shade. You will want to water to prevent drought stress while the grass is still actively growing, though. Light watering during dormancy will also prevent dehydration and watering in the early morning will decrease the risk of certain turfgrass disease. To learn more information about watering practices, visit our Lawn Irrigation Guide.
Fall Fertilization for St. Augustine
Fertilization differs this time of the year compared to the other active growing seasons for your St. Augustine. As previously stated, outdoor temperatures are starting to change, and so are soil conditions. Your grass is a living thing that needs specific nutrients at this time. Sod University recommends two different fertilizer options for the fall. You will only need to use one of the two options for fall fertilization. The Fall Fertilizer Box, in particular, has three separate bottles of fertilizer in it that help your St. Augustine lawn recover from the hot summer temperatures it just endured as well as prepare for the colder temperatures ahead.
In the early fall, you will start off with applying Boost to revitalize the green leaf blade color after the heat of summer. The rapid green-up of your lawn will last from the time of application through the remainder of the growing season with Boost’s time release formula. In the mid-fall, you should make an application of the second bottle in the box, Maintain, for well-balanced nutrition. Maintain serves to help with color retention late into the cooler months ahead and fortifies the root system to help it survive throughout dormancy or snow. In the late fall, you should apply Recover to prepare your lawn for environmental stressors of this colder weather.
Lawnifi Foundation is a slow-release granular fertilizer option that comes in a 25 pound bag and lasts for three months. With a 29-0-5 NPK formulation, Lawnifi Foundation is the perfect granular fertilizer for lawns and gardens. The two percent iron included in Lawnifi Foundation’s mixture helps plants carry oxygen throughout the leaves, roots and other parts of the plants to promote a green, healthy lawn. Featuring slow-release nitrogen, Foundation gradually feeds your lawn over an extended period of time without overwhelming your lawn with nitrogen during the fall. Both Lawnifi Foundation and the Fall Fertilizer Box cover 5,000 sq. ft. Learn more in Granular vs. Liquid Fertilizers or by clicking on the two products below. For more generic information about the Lawnifi brand, read Why Use Lawnifi Fertilizer?.
Fall Weed Control for Your St. Augustine
Your St. Augustine lawn has just made it through the summer months when it is not a recommended time for herbicide applications due to hot temperatures. Now that it is starting to cool down, you are free to apply both post-emergent and pre-emergent herbicides without risking any damage to your lawn. You may even notice that the weeds from summertime are starting to die off. Unfortunately, there are winter weeds that will start to pop up when the months are colder. A post-emergent herbicide controls any current weeds you are experiencing whereas a pre-emergent herbicide, as its name suggests, serves to prevent weeds from appearing. Fall is actually the best time to apply a pre-emergent—especially if winter weeds have been a big problem in the past years. You can also do this in the springtime around March or April. You can read more about pre-emergent applications in the fall in How to Use a Pre-Emergent Herbicide in the Fall. Some hard to control weeds that may appear around this time include chickweed, henbit, Poa annua, crabgrass or goosegrass.
If you decide to apply a post-emergent herbicide instead, it should be noted that centipedegrass and St. Augustinegrass are both sensitive to chemicals like 2,4-D, dicamba, MSMA and MCPP. A post-emergent containing the active ingredient Atrazine, like Southern Ag Atrazine and Spectracide Weed Stop For St. Augustine and Centipede Lawns are better options.
- Coverage: 50 lbs. covers about 12,500 sq. ft.
- Active Ingredient(s): Prodiamine 0.37%.
- Ease of Use: Requires granular drop or broadcast spreader for application.
- Best Used On/For: Established warm and cool season turfgrass before weeds appear.
Read product labels before application.
Pictured above: Poa annua.
Fall Insect Control for St. Augustine
It is better to apply an insecticide as a preventative as opposed to having to resolve an infestation once damage has already occurred—it’s probably less expensive too. Apply a broad-spectrum insecticide to prevent any harmful insects from taking over your St. Augustine. Although there could be a variety of insects that may be invading your lawn at this time, the main ones most universities recommend you look out for in your St. Augustine are grub worms. St. Augustine can also still have some problems with chinch bugs as well. Chinch bugs are usually the most active in the months of June–early September, but may still be present in some lawns such as St. Augustine. If you have insect activity, treat with an insecticide labeled to treat the insect you are seeing. If you use a granular variety, water the lawn immediately after application to help with absorption. Visit our Insect Identification blog for more details.
- Coverage: 30 lbs. cover between 16,000–21,000 sq. ft.
- Active Ingredient: Imidacloprid 0.5%.
- Ease of Use: Requires a drop or broadcast spreader for application.
- Best Used On/For: Broad-spectrum systemic formulation that offers preventive and curative treatment of insect control in turfgrass and landscape ornamentals.
Read product labels before application.
Fall Fungus Control for St. Augustine
This is the time of year for fall fungus outbreaks like gray leaf spot and large patch. If large patch or other diseases are a common problem in your St. Augustine, apply a fungicide at a preventative rate. This will help the grass enter colder months in a healthier condition. If you have had a fungus before, you may need to make multiple applications in affected areas. If you use a granular variety, water the lawn immediately after application to help soil absorption. Consider mapping those areas because fungicide treatment can be expensive.
- Coverage: One bottle covers 2,500 sq. ft.
- Active Ingredient(s): Propiconazole 1.45% and Lamda-cyhalothrin 0.08%.
- Ease of Use: Hooks up to your garden hose for an even spray application.
- Best Used On/For: Outdoor topical/contact fungus and general insect control.
Read product labels before application.
Pictured above: An image of large patch.
Lastly, lawn patch work and light topdressing with a sand and topsoil mix is a great way to recover any weak areas in your lawn that were caused by the summer heat. If you notice any hot spots, apply a light layer of topdressing to help it recover.
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