Light Green Patches After Crabgrass Preventer Application

Why Some Spots Stay Pale Green in Spring

After applying crabgrass preventer with fertilizer, random 1–2 ft diameter light-green spots may appear due to:

• Slow-greening cultivars: Some grass varieties green up later. If you overseeded last year, these may be those patches.
• Grassy weed invasion: A lighter-green weed (e.g., annual bluegrass, rough bluegrass) may be spreading. Pull a blade and compare to main lawn.
• Higher fertilizer need: Some cultivars require more nitrogen. Spot-treating is difficult.

What to Do

Monitor for a few weeks. If color equalizes, it was cultivar variation. If patches expand and differ in texture, it's a weed—consider selective control next season.

No immediate action needed unless weeds are confirmed.