Development of defensible space is outlined in fact sheet 6.302, Creating Wildfire-Defensible Zones. Colorado has great diversity in climate, geology and vegetation. Home and cabin sites can be found from the foothills through 10,000-foot elevations. Such extremes present a challenge in recommending plants. While native plant materials generally are best, a wide range of species can be grown successfully in Colorado.
Many plant species are suitable for landscaping in defensible space.
Use restraint and common sense, and pay attention to plant arrangement and maintenance. It has often been said that how and where you plant are more important than what you plant. While this is indeed true, given a choice among plants, choose those that are more resistant to wildfire. Landscape according to the recommended defensible-space zones. That is, the plants near your home should be more widely spaced and lower growing than those farther away.