It seems like summer only just arrived, and it’s already time to start thinking about fall maintenance tasks around the lawn. The warm-season grasses typically grown in Texas go dormant at the end of the year, and they’re going to need a little extra attention in the late summer or early fall to help keep them healthy.
The most important thing you can do in the fall for a warm-season lawn is stop fertilizing at the right time. Too much fertilizer late in the year can stress the grass while skipping the last fall application can weaken grass so it doesn’t get through the winter as well.
Fertilizer Timing
Using a lawn fertilizer containing nitrogen triggers lush fall growth, which helps choke-out winter weeds. The timing for your last fertilizer application depends on the first frost date in fall, which is determined by location.
In northern Texas where the average first frost date is November 1, apply fertilizer by September 15. For parts of Central Texas, including the Dallas area, where the average first frost date is November 16, apply fertilizer by October 1. Warmer parts of east-central Texas where the average frost date is December 1 should be fertilized by October 15. For southern Texas, including areas where it doesn’t freeze, apply fertilizer by November 1.
Application Rates
As a general rule, apply 1/2 to 1 pound actual nitrogen per 1,000 square feet of lawn space. To find out how much nitrogen a fertilizer contains, you’ll have to look at the N-P-K ratio on the fertilizer packaging. The first number in this ratio tells you what percentage of the fertilizer is made up of nitrogen.
A fertilizer with an N-P-K ratio of 30-0-6, for example, contains 30% nitrogen. You’ll have to apply 1-2/3 to 3-1/3 pounds of fertilizer per 1,000 square feet to supply 1/2 to 1 pound of actual nitrogen. Always read and follow the label directions for your specific fertilizer. For best results, use a spreader to apply dry fertilizer evenly. Across the lawn.
Other Fall Tips
Continue mowing while the grass is actively growing. Growth of warm-season grasses won’t slow down until the weather starts to cool, so be sure to keep up with the mowing until that happens. After the lawn starts to go dormant, you can cut back on mowing and eventually stop altogether unless you overseed with ryegrass for winter color.
Removing weeds before the grass starts to go dormant will help prevent them from taking over the lawn during the winter. Dormant grass isn’t competing with weeds, so the weeds are more likely to get out of hand during the winter than at other times of the year. To control annual weeds, apply a preemergent herbicide in the late summer or fall once nighttime lows reach 55 to 60 degrees Fahrenheit for four consecutive days. For perennial weeds, spot-treat with a post-emergent herbicide using a garden sprayer.
