Maintaining a healthy lawn is the first step toward weed control. Fertilize three times a year beginning with a slow release 3-1-2 ratio fertilizer such as 19-5-9 or 15-5-10 in late March-early April, then again using the same formula late June-early July. In the fall months of October-November, apply a winterizer fertilizer formula 18-6-2 or 8-12-6. The grass must be thick enough to crowd out the weeds.
Mowing to maintain an adequate leaf surface between 2-3" is directly related to a healthy root system. The leaf surface provides food for the roots and in turn the roots supply the leaf surface with nutrients. When the grass is mowed too short, the roots will shorten and become less adequate to survive heat and drought stress allowing weeds to invade the weakened areas. Mulching mowers help reduce thatch build-up and return needed nutrients to the soil. Water the lawn deeply and less frequently to create a deeply rooted lawn.
Apply pre-emergent herbicide granules in the early spring February-March before the grass begins actively growing and before weed seeds begin to germinate. Apply again in October-early November. Barricade is a safe pre-emergent granular herbicide that treats grassy and broadleaf weeds. Avoid weed and feed fertilizer formulas that can adversely effect trees and shrubs. In the flowerbeds, a similar approach is taken to prevent weeds with pre-emergent herbicide granules designed for the garden applied in the early spring and fall. Be aware that any annual or perennial seeds in the garden will also be eliminated.
Mulching is a critical component to weed control as well as conserving water, moderating soil temperatures, and adding organic matter that will gradually breakdown and improve the health of the soil. Weeds that may come up in the mulch are much easier to pull.
