Colorado lawns provide challenges for homeowners that lawns in many other parts of the country do not. Because of Colorado's mountainous terrain and seasonal drought periods, homeowners must adapt their land by amending the soil and frequently watering their plants. Additionally, Colorado homeowners must cope with the challenges of gardening at higher elevations with shorter summer seasons. To plant and grow grass seed, ensure that the soil is prepared and the seed is well-watered.
Test your soil up to three months before planting grass seed. Colorado State University maintains a soil-testing facility through its community and continuing education program. Contact your local county extension service for instructions on how to collect a soil sample and where to send it.
Apply soil amendments based on the recommendations made in Step 1. Common recommendations for amendments to Colorado soil include organic material such as compost or well-rotted manure to improve drainage, soil structure and nutrient content as well as nitrogen fertilizer (10-0-0) at a rate of 2 lbs. per 1,000 square feet, and powdered limestone to raise the pH of soil or sulfur to lower the pH.
Break up your soil to a depth of 6 inches with a rototiller. Spread the amendments over the soil to a depth of 4 inches. Mix these amendments into the soil with the rototiller and regrade the soil with a rake so that it slopes away from your home. Remove large rocks and debris as you work in amendments and regrade your lawn.
Sow cool-season grass such as bluegrass or fescue in mid-August through mid-September. Sow warm-season species that include Bermuda grass or buffalo grass from late May through mid-July.
Place seed in a broadcast spreader and distribute it by walking an even path over your lawn. Place a second layer of seed by walking a path perpendicular to your first route. Mulch with straw to prevent erosion.
Water your grass seed with 1/3 inch of water up to three times daily for up to three weeks to help grass seed germinate. Your soil should remain saturated during this time. Once grass germinates, taper off watering until you water only once every seven days at a rate of 1 inch per watering session.