Crabgrass can run rampant in the summer. Hot summers with adequate rainfall push summer weeds like crabgrass along. Crabgrass is a warm-season annual grass meaning that it thrives under hot and moist conditions. The high rainfall during germination (late April and early May) coupled with the wet and warm conditions of summer providers is the perfect growing conditions for crabgrass.
Annual Grassy weeds can cause havoc to a lawn. Dandelions, clover, crabgrass, dollarweed, and others invade quickly and spread relentlessly.
Pre-Emergents: Help Prevent the production of grassy weeds but do not completely eliminate them.
Post-Emergents Treat actively growing weeds with a systemic weed killer so you keep the grass you have and kill the weeds you want to get rid of. It will take longer for the weeds to die but they will.
Using Weed Preventers
Preemergent herbicides, or weed preventers, control crabgrass and other weeds by stopping their seeds from germinating. An application early in the growing season works wonders; it’s like vaccinating your lawn against weeds.
Why timing matters: Pre-Emergent weed preventers are not effective against weeds that have already begun to grow, so you must apply them before germination to gain any benefit. Crabgrass, the primary target of lawn weed preventers, can drop over 150k weeds in a life time so it is essential to get a pre-emergent on these weeds to keep them undercontrol for the summer months. At the same time that you are spreading weed preventers, apply lawn fungus treatment if needed.