As the ambient temperatures begin to stay consistently warmer, the soil temperatures will begin to warm up as well. When soil temperatures reach 64 ֯ Fahrenheit and stay at or above this temperature consistently for at least a week or longer, your lawn will begin to come out of winter dormancy and green blades will begin to emerge; however, there are other strategies that you can incorporate to help this spring green-up occur at a faster rate.

1. Adjust your lawnmower blades & bag the lawn clippings.

Although it is not recommended to “scalp” your warm-season turf grass in its growing season or prior to winter, it can be a beneficial practice in the late winter or early spring. The most appropriate time to scalp your lawn is just before spring green-up. Scalping your lawn too early can expose the crowns and stolon to frost or extremely cold temperatures. Scalping during the sod’s growth can cause undue stress and can potentially injure your sod, as well as slow down its growth rate as it focuses on recovering instead of growth. So, if you miss your window, please skip this step.

Scalping your lawn at the appropriate time can result in earlier spring green-up and can even help control some broadleaf winter weeds. Additionally, scalping and collecting/bagging the lawn clippings post-scalping will remove some debris that could otherwise contribute to an undesirable thatch build-up.

Most warm-season sod varieties grow and spread through rhizomes and stolon, which makes these varieties more susceptible to thatch accumulation. Take extreme caution when scalping your St. Augustine lawn. When the stolon, or runners, are at the surface of the thatch, you may cause an exceptional amount of damage to this essential plant part, which will cause injury and could possibly even kill your lawn.

While some thatch, about a ¼ inch to a ½ inch, can be beneficial to your lawn; however, too much accumulation can lead to serious lawn problems such as water issues, reductions in nutrients and air penetration into the soil, and an increase in insect and disease damage. This decline in the sod’s quality makes it much more difficult to manage your lawn. Further, sod will be less receptive to fertilization applications and your lawn will require much more water in order to keep the soil appropriately wet.

To assist your lawn in growing back healthy and strong, adjust your mower to a lower setting (½ inch to 1 inch) and mow your entire lawn. Once you are done mowing, remove the dead plant material to expose the soil to sunlight. This exposure will warm the soil for faster spring green-up.

We always suggest weighing the pros and cons of scalping before deciding if it is right for your lawn. Scalping your lawn incorrectly can lead to sod injury or death, so please make sure to practice great caution and follow all the proper guidelines if you decide to scalp your lawn. You might even decide it is better to hire a landscape professional to ensure this is done properly.

2. Aeration and Topdressing

 Aeration is a beneficial lawn maintenance practice in which you remove cores or plugs of soil which will provide pathways so air and water can easily permeate the soil, which in turn will improve root and lawn health. Aerating is also beneficial to reduce soil compaction, stimulate root growth, increase your lawn’s drought tolerance, reduce water runoff, and decreasing thatch issues by increasing microorganism’s decomposition activities.

Aeration is recommended yearly and should be done when the sod is in an active growing season. Between March and April or September and October will be the most beneficial times to aerate. Additionally, to reduce weed issues, you should aerate your lawn before Texas’ heat arrives. This allows the lawn some time to grow back in. This will decrease the opportunity for weeds to pop up in the tiny holes that are left behind after aeration.

It is best to aerate on a day when temperatures are mild. Additionally, aerating when the soil is moist will make it easier to penetrate. Make sure the soil is not too wet, however, as this can lead to soil compaction issues. Although you can use a garden spade to aerate, it is much more efficient to rent a power-driven core aerator. You may leave the soil cores/plugs on the surface of the lawn to be broken down by rain and irrigation, but you may also remove them if their appearance is bothersome.

Further, it is beneficial to aerate and apply topdressing at the same time; however, topdressing only needs to be done about twice per year, depending on the health of your existing soil. The amount of soil compost blend should not exceed an 1/8 inch, as it may prevent movement of water into the soil. Topdressing will jump-start your growth by adding vital nutrients to your soil, as well as increase microorganism activity and prevent layering issues.

3. Pre-emergent Application

Weeds are one of the most common lawn problems for homeowners. Beyond inconveniencing the homeowner’s valuable time, weeds also cause health issues for the lawn. Weeds will compete with your sod for sun, water, nutrients, and air. Additionally, since weeds grow at a faster rate than sod, they usually win if allowed to grow out of control.

Texas weather is typically warmer than in other states in the U.S. Therefore, most experts suggest that pre-emergent applications should be done in late winter or early spring. It is essential to apply pre-emergent before weeds begin to grow for the herbicide to work effectively. Pre-emergent work by coating the newly germinating weed seeds with the herbicide chemical. Then, as the newly forming roots begin to absorb moisture from the soil, they also absorb the herbicide chemical.

Pre-emergent should be applied before the soil temperatures get above 55° Fahrenheit. Pre-emergent are very un-soluble and are mostly broken down by microbes in the soil. These microbes are controlled by soil temperatures, just like the seed’s germination process. Because of this, applying the pre-emergent earlier rather than later is more effective because it will typically remain active in the soil until it is time for them to do their job as the weed seeds begin to form their first root.

If you will be fertilizing and applying pre-emergent around the same time, you should apply the fertilizer first, wait a few days, and then apply a granular pre-emergent. Watering in the pre-emergent properly will allow the pre-emergent to create a thin barrier near the surface of the soil, which is where the seeds remain until they sprout.

Additionally, please follow the product’s label instructions to ensure proper application. For example, the label should indicate mowing restrictions because mowing can negatively affect the product’s efficacy.

4. Apply Fertilizer

The recommended time to apply a fertilizer in our area is mid to late April, when the sod is usually beginning to grow; however, as you begin to see new green blades of sod emerge in the spring indicating the sod is growing, an application of fertilizer can be used to help speed the process up. Applying a fertilizer too early can force the sod into vigorous top growth instead of focusing on a stronger root system.

Soil tests can be a great tool to determine what fertilizer ratio to use on your lawn. Many soils in our area are low in nitrogen and potassium and high in phosphorus. However, this can vary depending on your region, the type of soil added pre-install, the amount of soil added before installation, how much time has passed since the installation, amount of rainfall and irrigation over the previous year(s), and several other factors. If you will not be facilitating a soil test, a general rule of thumb would be using a product that has a 3-1-2 ratio or a 4-1-2 ratio (the 1st number represents nitrogen, the 2nd represents phosphorus, and the 3rd potassium).

There is no one fertilizer that is recommended over another. Just follow the general ratio rule above if not basing your lawn’s needs off soil test results. Additionally, always check the label to ensure it is safe for your sod variety and follow all the instructions and safety warnings.

5. Rake/Remove Debris

Just as you do not want the thatch building up more than ¼ to ½ inch, you will also want to remove the debris build up that accumulated over the winter season, such as leaves, moss, and sticks. By doing so, you will ensure that your lawn is receiving the benefits it needs from irrigating, rainfall, mowing, sun, and airflow. Additionally, the dense buildup can retain moisture and inhibit disease, such as fungal growth. Particularly when overnight temperatures are cooler.

6. Increase Irrigation

As we move into warmer temperatures, your lawn will require more moisture. This is a good time to have your irrigation system inspected to ensure all components are working properly. The warmer the temperatures get, the more water your lawn will need. Additionally, you want to water early in the morning to avoid evaporation and to prevent fungal growth.
The amount of water your sod needs will vary depending on the variety. For example, in general, sod needs about 1 to 1.25 inches of water per week during its growing season. However, if you have St. Augustine, you may find that you need to be watering twice a week, particularly if it is planted in full sun. Please check with your regional Ag Extension if you are unsure how much water your lawn needs weekly. For slopped areas, visit this article for more information and procedures.