Lush green lawns are the cornerstone of many people's view of an attractive home landscape. Weeds can often invade those lush green lawns, especially in years of drought. Colorado is home to a number of invasive weeds that can invade your lawn. By keeping your lawn properly irrigated, you can reduce problems with these and other weeds.
Dandelions are common weeds throughout Colorado. Thin lawns or drought-stressed lawns in Colorado can be more susceptible to dandelion infestations than lawns that are thicker and receive adequate water. Although there are many herbicides that can kill dandelions, there are a couple of different ways to deal with dandelion's naturally. If you don't have many dandelions, digging them with a long dandelion fork can often get enough of the weed's roots to prevent its return. If you have a serious dandelion problem, it could be an indication that the pH of your soil is too high, or above 7.5. Consider having your soil tested and, if it proves to be too high, add sulfur to your lawn to lower its pH.
Crabgrass is also common throughout Colorado. As with dandelions, thin or drought-stressed lawns often are ideal supports for crabgrass. However, crabgrass can sometimes be a problem in areas of your lawn that get less irrigation than other parts. If you are trying to get rid of crabgrass in the fall, doing nothing may be your best course of action. According to Colorado State University, crabgrass is killed by fall frosts. Once killed, dig out the crab grass and re-seed the area in the spring. The most effective way to naturally control crab grass growth is to keep your lawn seeded thickly and keep it very well hydrated. Many herbicides, however, work well on crab grasses. Those herbicides include: benefin, trifluralin, bensulide and dithiopyr, among many others.
Foxtail is a shallow rooted annual grass that can grow very quickly and harm your lawn. Foxtail is seeded by nearby plants and can grow tall enough to shade out your lawn. Foxtail roots secrete an herbicide that can harm nearby plants, including the grasses in your lawn. If your foxtail infestation is localized, you can add a couple inches of mulch to starve the plants of light. Once you have killed them, re-seed the patch of lawn. Pulling foxtails also works well. You can also simply mow the grass to prevent seed drops. Foxtail will freeze over the winter. By preventing re-seeding via mowing, you can seed the infested areas in the spring to repair any damage this weed has done to your lawn. Foxtail also responds well to pre-emergence herbicides that kill the plant before it has the chance to grow.