Weed IPM uses physical, mechanical, cultural and biological methods first to control weed populations. Aggressive weeds can crowd out grass and other desirable plants, so proper fertilization and irrigation is important. Use chemical control in combination with other methods, when other methods have failed, and/or are cost prohibitive.
- Mow as high as practical during the summer months.
- Mow often enough so that no more than one-third of the grass blade is removed in a single mowing.
- Irrigate properly to help reduce annual weed infestation.
- Fertilize according to the needs of your grass species.
- Aerate the turf at least once a year to reduce compaction and control thatch.
- Mulch with organic or inorganic materials to prevent annual weeds.
- Prune or remove flower heads of weeds to limit seed production in April for winter annual and summer for summer annuals.
- Remove annual weeds by hand. Hand removal of perennial is seldom effective.
- Use biological agents such as insects.
Click here to learn more about leafy spurge, a noxious weed in Colorado.
Soil solarization is a nonchemical method for controlling soil borne pests, including weed seeds, during hot summer months.
Interested in learning about organic turf? The City of Boulder sponsored “A systems approach to managing turf” workshop.
Why do we care about weeds?
Weeds reduce crop yield by competing for water, light, soil nutrients, and space. They can serve as hosts for diseases or provide shelter for insects to overwinter. Also, some weeds produce chemical substances that are toxic to crops, animals or people.
There are some benefits provided by weeds. They can provide nectar for pollinators and habitat and feed for wildlife. They can add organic matter to soil and may help stabilize soil.
Weed Identification — correctly identify the weed first!
Flame Weeding for Vegetable Crops, National Sustainable Agriculture Information Service
Noxious Weed Management Program, Colorado Department of Agriculture