1. This has a 1-2-3 of its own. First, water only monthly this time of year. Water deep enough that you don't have to water again until next month. If it rains, then don't water. Second, always mulch mow St Augustine at your mower's highest setting every week during the growing season. There is never a need to lower the deck for St Aug. Third, fertilize with a good organic fertilizer at 10-20 pounds per 1,000 square feet on the federal holidays. Thanksgiving is the next one. In Dallas you can start in late March (no federal holiday for reference but I start on Washington's Birthday, Memorial Day, 4th of July, Labor Day, and Thanksgiving). Those three things should keep your grass green. There is one exception. If your grass turn yellow following 3 days of torrential rain, then apply greensand at 40 pounds per 1,000 square feet. As with most organic materials, it takes 3 full weeks to see results from greensand.
2. Go to a garden center or big box store and find a Weed Hound tool. It's about $25. It allows you to pluck weeds out of the ground from the standing position. It is perfect for Dallis grass. You can pluck them out as fast as you can step on them.
3. Fire ants are protein ants and they hate sugar. If you spray your yard with diluted molasses, they will leave. Dilute it to 3 ounces per gallon. I use a hose end sprayer like the Ortho with a dial. Spraying molasses on a cold day is a problem so you could dilute it by half with water going into the sprayer and double the rate to 6 ounces per gallon. You can also use the 3 ounce per gallon mix as a drench into the mounds. Drench each mound with at least 1/2 gallon of mix. If you want to kill the ants with the drench, you could add a couple ounces of orange oil to the molasses mix when you drench.
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