Ongoing research continues to disclose the health hazards of chemicals used to control weeds. They have been shown to affect people and plants including those under the soil surface. For example, 2-4-D, used for selective weed control in turf is a proven carcinogen. There are many alternatives to use in place of chemicals for weed control. Weeds are evidence of nature working to restore natural succession and biodiversity. Large areas of bare soil are not natural and should be covered or planted to avoid not just weeds, but erosion from natural forces. Anything that covers the bare ground will discourage the weeds.
To control weeds:
- Probably no other factor contributes more to weed problems than irrigation systems over scaled for their respective landscape. Converting to a drip or microsprayer irrigation system whenever possible, converting to a drip or microsprayer irrigation system, designed to water only desired plants and purposely leaving areas dry will greatly reduce weed occurrence. Lawns would be one of the few exceptions.
- Natural mulches discourage weeds and return badly needed organic matter to the soil. Mulch layers need to be replenished as they break down or they will provide a great environment for a new crop of weeds.
- Plant unused areas to attract beneficial insects. Insectary plantings will cover unused ground and compete with weeds. As an added bonus, they will provide screening and habitat for beneficial insects and other wildlife. Nurseries and mail order companies offer special insectary seed mixes.
- Plant cover crops to compete with the weedy species. Insectary type plants, ornamental grasses, and/or a selected seed mix will occupy space where weeds once grew, and will increase the garden’s biodiversity. Some, such as legumes, can even add nitrogen to the soil. Cover crops can be managed with the proper equipment with very little effort.
- Mechanical weed control is, in many areas, a viable alternative to the use of herbicides.
- Improve the health of turf to out-compete weeds. With improved irrigation systems and practices, improved maintenance and cultural practices (which could include recycler mowers, aerating and the use of organic fertilizers), turf grass will out-compete most weeds.
- Technology is offering additional alternatives such as flaming, steaming and solarizing, methods using special apparatus to kill weeds by heat.