The best time to fight crabgrass with pre-emergent herbicide is when forsythias tend to bloom. In the mid-Atlantic region, this is usually between April and May. Even if you're late to apply the herbicide, it’s effective as long as the crabgrass plant has fewer than five leaves.

Vinegar is known to be a contact herbicide, which means it kills the foliage it comes in contact with. Because of the high acetic acid concentration, horticultural vinegar kills weeds and grass more effectively. However, keep in mind that high amounts and multiple applications can affect the soil by lowering the pH levels.

Sealing pavers helps cut down on weed growth, but it won’t wipe it out entirely. What it does really well is harden the joint sand—especially if you’re using a sealant with polymer additives—so weeds have a much harder time breaking through. It also blocks airborne seeds from settling in the cracks and keeps debris from building up. This results in fewer weeds, easier maintenance, and a cleaner-looking surface. Just remember, sealing is a strong defense—not a one-and-done solution. Stay on top of sweeping, spot-treating, and resealing every few years to keep your weeds in check.

Each type of weed comes with its own control methods, but stopping the seed spread is the first step. Grazing, mowing, and hand pulling can slow the invasion. In some cases, selective herbicide is necessary to stop a persistent weed from overtaking an area.