By Travis W. Gannon, Ph.D., and Fred H. Yelverton, Ph.D
Weed Science Society of America
If you're taking a chemical-free approach to home weed control, you've most likely discovered it can be a real challenge. Without herbicides in your arsenal, it can be tough to keep the invaders out of your lawn and natural areas, flower beds and vegetable gardens, walks and driveways. To succeed, you need time, persistence and a multifaceted approach. Try these nine proven techniques that can help:
1. Select clean seeds and plant material. When you are planting ornamentals, vegetables and grasses, purchase certified seeds and weed-free plants from a reputable source. You don't want to introduce more unwelcome guests into your home landscape.
2. Remove weeds before they go to seed. Some varieties of weeds can produce tens of thousands of seeds from a single plant, multiplying your weed control problems for years to come. So make certain you remove weeds around your home before they flower and produce seeds.
3. Keep the local climate in mind. Select species and cultivars appropriate for the planting conditions around your home. Consider the climate, amount of sun or shade and expected rainfall. If the plants you select are a good "fit," they are more apt to thrive and to compete with weeds.
4. Create a barrier. For further weed suppression throughout the growing season, apply two to three inches of mulch or use landscape fabric or black plastic to deter weeds.
5. Focus on "culture." Cultural practices — how you prepare the soil and tend to what you've planted — will help your plantings stay healthy and compete with weeds for light, moisture and nutrients. Read about what you're growing and focus on the basics, from pH levels to timely irrigation and fertilizer.
6. Turn to tools. A hoe, tiller or even hand-weeding can work, especially if the space you're tending is fairly small.
7. Keep it clean. Keep your garden hoe, spade, mower, tiller and other outdoor tools clean to keep from spreading weed seeds or plant parts that you encounter.
8. Establish a perimeter. Pay special attention to the area adjoining your flower bed, garden, natural area or lawn and establish a weed-free perimeter. Mow or mulch the area or pull or dig up weeds as they emerge. You'll help to reduce the number of new weed seeds in the area you want to protect.
9. Pay special attention to perennial weeds. To manage perennial weed species effectively, you'll likely need a multifaceted approach that uses many of the techniques above. But proceed with care. It can be tough to dig up perennials and the underground tubers and rhizomes they use to spread without leaving fragments behind. New weeds can grow from any pieces that break off and remain in the soil. Another strategy is to cut off the emerged green part of the weed with your hoe or mower — repeating the process quickly each time it regrows. Without leaves needed for photosynthesis, the underground plant parts will become weakened and may eventually die.
Unless you are tending a very small area and have lots of time to devote, you most likely won't achieve the same level of weed control with chemical-free techniques that you would with an herbicide. But reset your expectations and have faith. Each year that you prevent weeds from going to seed or spreading underground, the easier your weed control task will be in years to come!
This column is provided as a courtesy by the Weed Science Society of America (WSSA). The authors Travis Gannon and Fred Yelverton teach and conduct research in weed management at North Carolina State University.