Every spring, homeowners get the itch to get out and work on their lawn the moment temperatures tick above 60°F. But starting too early — especially with fertilizer or herbicides — can actually set your lawn back. Here's how to time things correctly.
Watch Soil Temperature, Not Air Temperature
The most reliable trigger for spring lawn care is soil temperature, not the calendar date. Warm-season grasses like Bermuda and Zoysia (the most common in Oklahoma) break dormancy when soil temps consistently reach 55–65°F at a 4-inch depth.
In the OKC metro area, that typically happens in late March to mid-April, depending on the year. You can check local soil temps at weather.gov or through OSU Extension resources.
First Mow of the Year
Wait until your Bermuda or Zoysia shows clear signs of green-up — at least 50% of the lawn should be actively growing before you mow. Mowing dormant grass tears at the crowns and stresses the plant.
When you do mow for the first time, consider a slightly lower cut (scalping) to remove dead thatch and let sunlight reach the soil. This accelerates green-up but should only be done once, in early spring.
Fertilizer Timing
Do not fertilize until your lawn is actively growing — usually when it's about 50% green. For most of Oklahoma, this means:
- First application: late April to early May
- Using a slow-release nitrogen fertilizer prevents burning and feeds the lawn evenly
- Applying too early pushes leaf growth before root systems are ready
Pre-Emergent Weed Control
This is where timing is most critical. Pre-emergent herbicides (for crabgrass, spurge, etc.) need to go down before soil temps reach 55°F — typically late February to mid-March in central Oklahoma.
Miss this window and you lose your best chance at weed prevention for the year. If you're not sure, a professional lawn spray service will know exactly when to apply for your zip code.
Oklahoma Spring Lawn Calendar (Bermuda / Zoysia)
- Late February – March: Pre-emergent herbicide application
- Early April: First mow / scalp if needed
- Late April – May: First fertilizer application, begin regular mowing
- May: Post-emergent weed spray if needed
The easiest way to stay on schedule is to work with a local lawn care provider who knows your area's micro-climate. QuoteLawn connects you with providers who handle the timing so you don't have to think about it.