Winter time duties for your lawn doesn’t involve a lot of work! You’ve worked hard for your lawn all spring and summer long. Now is the time to do less, spend less, and enjoy more family time.
The biggest thing to prep for cooler weather is to turn off your irrigation completely. Even warm season grasses like we have in south Texas do not need a lot of water when daytime temps are rarely getting over 75. Good rule of thumb is to try and turn your irrigation off around November 1. With winter in our area, it typically brings on the rainy season, giving you even more reason to turn it off until March 1 of the next year. By limiting the amount of water going down, you’re going to limit fungal and winter-time broadleaf weeds from coming up. Doesn’t matter if you have Bermuda, Zoysia, or the most common, St. Augustine. They all are going to need limited watering needs and will go dormant when we freeze or get close to freezing.
If you do have an irrigation system, it’s very important to make sure your backflow preventor has a winter sleeve. You also need to ensure that your water flow is turned off and the 2 flathead screws are turned in the opposite direction. If and when we do have a deep freeze, exposed pipes need to be covered. Not only covered by a sleeve but all exposed fittings need to be wrapped with foam and tapped up. I can tell you that I had a sleeve on my preventor in the freeze of 21, but I still got damage. What got me was that not all of my fittings were covered with foam. A sleeve alone is not enough to ensure you are protected. If you are unsure of what to do, by all means, call a licensed irrigator such as Irrigation Design Services at 713-460-8185 or Andy’s (https://www.sprinklerdrainage.com/houston-location/).
Fall is the time to put down a fall fertilizer. You really need to get this down by November 15th at the latest if possible and as early as October 15th or when the temps start to break from the summer norm. It’s also a good time to put down a pre-emergent along with the fertilizer. A more soil friendly pre-emergent is Prodiamine. There are many options here. Organic fertilizer like MicroLife Brown Patch is a good option. Especially if you have St. Augustine as it will help fight the fungus. Putting down MicroGro, another product from MicroLife will help with conditioning the soil to help with not only root development but fight off harmful fungi that cause the fungus in the first place. These products can be purchased at Ace Hardware, Plants for all Seasons, among other specialty nurseries. Big box stores will not carry them.
If you are less on the organic side, Nitrophos fall fertilizer is an option. It is a synthetic fertilizer so if you have fungus already present, I do not recommend it. Adding any kind of synthetic fertilizer to existing fungus is like throwing kerosene on an open flame. It will get worse. The key with fall fertilization whether it is organic or not is that it does not contain a lot of nitrogen. At this point in the season, you likely have put down or absorbed enough nitrogen for your grass type. You really are looking for more lateral root growth instead of grow, grow, grow like you want in the spring. The NPK, or nitrogen, phosphorus, and potassium, respectively, does have meaning here. Clay soils are already naturally high in phosphorus so you really need very little at any time of the year. What you want to add more of anything here is potassium to encourage the lateral root growth. Again, there are many options to choose from!
If you have St. Augustine grass, fungus is going to be your worse enemy going into fall. If we’ve had a rainy season, it might be inevitable to some degree. You can try and alleviate with a few different actions.
Even Zoysia and Bermuda can get fungus but it has to be really wet and a lot of nitrogen at play in order to develop fungus. The same steps described above will help alleviate or keep the fungus from coming in the first place. The best offense against fungus is a good defense. The more things you do to try and keep it from coming in the first place, will pay dividends later. If you have active fungus, you really only have a few options. MicroGro, which, is not labeled as a fungicide by the way, put down heavily in the areas that area affected. Or, turn to the fungicide. The timing interval is typically 14-21 days after the first application. Meaning, you will likely have to apply a second time to knock it out. You can also throw some a quality, leaf mold or fungal based compost down and this may cure it as well. If you do decide to use the fungicide, just understand that it is typically a band-aid and will likely return in the same spot, year after year. That’s not the only drawback with using synthetic fungicides.
When you put down the fungicide, you’re destroying a lot of the good biology in the soil so the next year, you’re really going to need and replenish your soil with good biology in the form of compost, organic fertilizer, compost tea, or some other good microbes to help recover what you have lost. By not replenishing, your soil is going to be even more susceptible to fungus the following year.