When to Apply Weed Control in Tulsa
The best time to apply weed control in Tulsa depends on the type of weeds you're fighting. For pre-emergent control of crabgrass and other summer weeds, apply in late February through early March when soil temperatures reach 55°F. For post-emergent control of active weeds, apply when temperatures are between 50 and 85°F and weeds are actively growing. For winter weeds like henbit and chickweed, apply pre-emergent in late August through September.
Understanding Tulsa's Two Main Weed Seasons
Living in northeastern Oklahoma, we deal with two distinct weed seasons that require different timing and strategies. The key to effective weed control isn't just about what product you use — it's about timing your applications to match our local weather patterns and soil conditions.
Spring/Summer Weeds (March–September)
These include crabgrass, dallisgrass, spurge, goosegrass, and various broadleaf weeds like dandelions and clover. These warm-season weeds germinate when soil temperatures warm up in spring.
Fall/Winter Weeds (September–April)
These include henbit, chickweed, poa annua (annual bluegrass), and rescuegrass. These cool-season weeds germinate in fall when temperatures drop.
Pre-Emergent Weed Control: Your First Line of Defense
Pre-emergent herbicides prevent weed seeds from germinating. Think of them as creating an invisible barrier in your soil that stops weeds before they even sprout. This is always your most effective and economical approach to weed control.
Spring Pre-Emergent (Late February – Early March)
Apply when soil temperatures reach 55°F for three consecutive days. Don't wait until you see weeds — by then it's too late. At Complete Lawn Care, we monitor soil temperatures and typically apply our first pre-emergent in the first week of March, sometimes late February during early warm spells. Recommended products: • Prodiamine (Barricade): Lasts 3–6 months, excellent for crabgrass • Dithiopyr (Dimension): Has some early post-emergent properties • Pendimethalin (Pendulum): Budget-friendly, lasts 2–4 months
Fall Pre-Emergent (Late August – Mid-September)
Apply when soil temperatures drop back to around 70°F, typically early to mid-September in Tulsa. This prevents winter weeds like henbit, chickweed, and poa annua from taking over during fall and winter. This is the application most homeowners skip — and then wonder why their lawn is full of purple henbit flowers in March. Recommended products: • Prodiamine: Works well for winter weeds • Dithiopyr: Another solid choice • Many combination products work for both seasons
The Split Application Strategy
For the best control, many professionals — including Complete Lawn Care — use a split application approach to maintain protection throughout the entire growing season.
First Application
Early March at full rate or slightly reduced. Creates the initial protective barrier against summer weeds.
Second Application
Late May or early June at half rate. Catches any gaps as the first application breaks down, extending coverage all season.
Post-Emergent Weed Control: Dealing With Active Weeds
Sometimes weeds slip through despite pre-emergent, or you're starting mid-season and need to clean up existing weeds. That's where post-emergent herbicides come in.
Apply When
• Air temperatures are between 50 and 85°F • Weeds are actively growing (green and lush) • No rain is expected for 24 hours • The lawn is not overly stressed
Avoid Applying When
• Temperatures exceed 85–90°F • Your lawn is drought-stressed • Within 2 weeks of seeding • Frost is expected within 3 days
Summer Heat Warning
If the forecast high is above 85°F, apply very early in the morning or wait for cooler weather. Above 90°F, avoid post-emergent applications entirely. Sometimes it's better to tolerate a few weeds through the worst heat and address them in September.
Common Tulsa Weed Problems and Solutions
Crabgrass
Prevention is everything — pre-emergent in March is 95% effective. Once crabgrass is up and growing, it's difficult and expensive to control. If you missed pre-emergent, products containing quinclorac (Drive XLR8) or fenoxaprop can control young crabgrass in Bermuda.
Dallisgrass
One of Tulsa's most frustrating weeds — a perennial clump grass that's extremely difficult to control. Pre-emergent helps prevent new dallisgrass. For existing plants, repeated applications of MSMA or manual removal. Multiple treatments over several months may be needed.
Nutsedge (Nutgrass)
That bright green, fast-growing 'grass' that pops up after rain — regular weed killers don't touch it. Use specialty products containing sulfentrazone (Dismiss) or halosulfuron (SedgeHammer). Multiple applications are usually needed because nutsedge reproduces through underground nutlets.
Henbit and Chickweed
Incredibly common winter weeds in Tulsa lawns. Best controlled with fall pre-emergent in September. If they're already up, post-emergent in fall or early spring works well. Don't wait until spring when they're flowering — treat them in fall when they're young.
Clover
Use three-way broadleaf herbicides — multiple applications may be needed. Interestingly, clover often indicates low nitrogen. A good fertilization program often naturally suppresses clover by encouraging thick, competitive grass.
The Complete Lawn Care 7-Step Program
At Complete Lawn Care, we've developed our 7-step program specifically for Tulsa's climate and the weed challenges we face here. This systematic approach, timed to Tulsa's weather patterns, provides consistent weed control while maintaining a healthy, thick lawn.
Step 1 — March
Pre-emergent application for summer weeds plus early spring fertilization.
Step 2 — April
Post-emergent spot treatment for any winter weeds that survived, plus spring fertilization.
Steps 3–5 — May through July
Fertilization with spot treatment for any breakthrough weeds, adjusted based on temperature.
Step 6 — September
Fall pre-emergent for winter weeds plus fall fertilization.
Step 7 — October through November
Late fall fertilization and any needed post-emergent for emerging winter weeds.
Why a Healthy Lawn Is Your Best Weed Prevention
The best weed control is a thick, healthy lawn. Weeds are opportunists — they fill in bare spots and thin areas. Complete Lawn Care's approach isn't just about spraying herbicides; we focus on building a lawn that resists weeds naturally.
Proper Fertilization
Strong, thick grass outcompetes weeds. A well-fed lawn naturally crowds out opportunistic weed growth.
Correct Mowing Height
Taller grass shades out weed seeds, preventing them from getting the sunlight they need to germinate.
Soil Health Testing
We recommend annual soil testing to identify and correct pH and nutrient deficiencies. Understanding your soil is critical to growing thick grass that resists weeds naturally.
DIY vs. Professional Weed Control
You can absolutely handle weed control yourself — if you're willing to stay consistent. The challenge most busy Tulsa homeowners face isn't ability, it's consistency. Missing your pre-emergent window by two weeks can mean the difference between a weed-free lawn and fighting crabgrass all summer.
DIY Requires
• Monitoring soil temperatures and weather closely • Purchasing and applying multiple products at the right times • Keeping detailed records of what you applied and when • Adjusting your approach based on results • Storing pesticides safely and following all label directions
Professional Programs Offer
Complete Lawn Care's 7-step approach takes the guesswork and timing stress off your plate. We monitor conditions, automatically schedule optimal application windows, and adjust our approach based on what we're seeing across Tulsa lawns every season.
Ready for a Weed-Free Lawn This Season?
Don't miss your pre-emergent window. Complete Lawn Care's 7-step program handles the timing, monitoring, and applications for you — so you can enjoy a thick, healthy, weed-resistant Tulsa lawn without the guesswork.
