Let's Grow: Healthy lawns reduce weeding chores
Are you fighting a losing battle with weeds in your landscaping? Weeds are the biggest challenge for landscape gardeners. We’ve tackled this topic from many directions in past columns, but here’s a new idea: It’s quite possible that the biggest source of weeds in your landscaping is the lawn surrounding your landscape beds.
Lawn grasses (and the weeds in your lawn) are eager to invade your landscape beds. There’s less competition there, and most likely the soil conditions are better. Chances are your lawn has quite a few weeds mixed with the lawn grasses. Weeds like ground ivy, nutgrass, clover, wild strawberry, Bermudagrass and bindweed will aggressively creep into your landscape beds, moving underground as well as on top.
Other weeds will invade your gardens by seed. Dandelions, crabgrass, nutgrass, and annual grasses can mature and produce seed between regular mowing. Even if you’re careful not to blow grass clippings into your mulch, wind will transport weed seeds from the lawn to the garden.
The solution is to eliminate lawn weeds. Simply feeding your lawn will help, since healthy turf grass chokes out many lawn weeds. Unless you re-seed regularly with new turfgrass seed, your lawn will give way to weeds eventually. Cutting at four inches instead of three helps also. So does core aeration (plugging). If your lawn is lush and healthy, weeds won’t thrive.
Turf professionals recommend treating your lawn every year with herbicides. The most common are 2-4-D broadleaf weed control spray and pre-emergent crabgrass control. Nutgrass, Bermudagrass and clover require specialized herbicides. If you take the trouble even once to knock out lawn weeds, and then keep the remaining turfgrass healthy, you will cut the weed population in your lawns and gardens dramatically.
Annual edging of gardens, landscape beds and mulch circles around trees is an essential part of spring grooming in your landscape. Bed edging is the restoration of a clean, sharp line between your landscape beds and the surrounding lawn, removing lawn grass that has crept into your landscaping during the past year. Without bed edging you’ll wind up with lawn underneath your foundation shrubs and invading your perennial border. If you allow this invasion you’ll have a very difficult time controlling it once the grass, weeds and desirable plants are all mixed together.
Bed edging is a three-step process. First, it’s helpful to mark the bed edges. Next, use a sharp, clean spade to cut straight down along the bed edge, three inches deep. Next, remove the strip of sod inside your cut, along with any grass or weeds that have gotten established inside the bed line. You should now have a “gutter” three inches deep all around you landscape beds. Then spread new mulch three inches thick all along the edges, feathering it out toward the center of the bed under established plants.
There’s no single magic solution to weed control in your landscape, but if you understand weeds you can defeat them using a simple system of controls. There are three basic kinds of weeds; Annual, biennial and perennial. Annual weeds come up from seed each year and die before winter. Biennial weeds grow the first year and bear seed the second year, and then die. Perennial weeds survive the winter and continue growing stronger each year, spreading underground and also by seed.
If you’re constantly fighting weeds in your landscape, take a good look at your lawn. Controlling lawn weeds is an essential step to keep your landscape beds weed free.
Steve Boehme is a landscape designer/installer specializing in landscape “makeovers”. “Let’s Grow” is published weekly; column archives are on the “Garden Advice” page at www.goodseedfarm.com. For more information is available at www.goodseedfarm.com or call GoodSeed Farm Landscapes at (937) 587-7021.