Weed Control
Grassy weeds are hard to control because grass killers will kill lawn grasses as well as weedy grasses. Grassy weed prevent, such as Halts or Team, can be applied in the spring when the first dandelion blooms to prevent crabgrass and around Labor Day to prevent annual bluegrass. Coarse grasses which grow taller than the lawn grasses can be controlled by using a paint brush to apply Roundup to the taller tips.
Weeds are either broadleaf, such as dandelions and chickweed, or grassy, such as crabgrass and annual bluegrass. Broadleaf weeds are easiest to control since many lawn weed killers will kill broadleaf weeds without harming grass. Its active ingredients is either Trimec or 2,4-D. Weed and feed fertilizers have to be applied evenly over the entire lawn even where there are no weeds. The best weed control is a thick healthy lawn that crowds out weeds. Weeds are a sign that the lawn is stressed, usually by poor soil, lack of regular watering, lack of fertilizer or mowing too short. I once visited a natural prairie area on the edge of a school yard. The school yard was so full of dandelions that they overlapped but there were no more than a handful of dandelions in the entire prairie. The dandelions ended right at the edge of the mowed area. Low mowing allows more sunlight to reach the soil which encourages weed seed growth while a higher mowing height causes the soil to be in deeper shade, which discourages weed seed growth.
Another common weed is moss. It is almost guaranteed to grow during the rainy season anywhere there is shade. By spring, moss will have killed out quite a bit of grass. It is better to use moss killer in early winter before moss smothers the grass. Almost all moss killers for lawns contain iron sulphate. It will stain concrete so sidewalks, driveways and patios should be hosed off immediately after moss killer is applied.
