When to Plant Grass Seed in Colorado: Lawn Growing Tips

Question When to Plant Grass Seed in Colorado?
Answer Spring (mid-April through May) and fall (late August to mid-September).
More Info
  • Spring Planting: After the last frost and when soil temperatures reach 50°F.
  • Fall Planting: Preferred for cooler temperatures and natural rainfall aiding germination.
  • Regional Considerations: Adjust planting times based on local climate conditions for optimal results.

When to Plant Grass Seed in ColoradoIn Colorado, the ideal times to plant grass seed are during the spring and fall. Spring planting should occur once the risk of frost has passed and soil temperatures have warmed to at least 50°F, typically from mid-April through May.

Fall planting is often more successful and is recommended from late August to mid-September. This timing takes advantage of cooler temperatures and natural rainfall, facilitating seed germination and strong root development before the onset of winter.

Given Colorado’s varied climate, adjusting planting times based on specific regional conditions is crucial.

Pennington Smart Seed Sun and Shade Grass Mix 3 lb
Pennington Smart Seed Sun and Shade Grass Mix 3 lb
Ideal grass seed for lawns that receive sun in some parts and moderate shade in others; Contains just the right amount of fertilizer to help your lawn succeed
Scotts Turf Builder Rapid Grass Tall Fescue Mix, Combination...
Scotts Turf Builder Rapid Grass Tall Fescue Mix, Combination...
Revolutionary mix of seed and fertilizer results in full, green grass in just weeks; This grass seed mix is for large problem areas in your lawn and establishing new grass

When to plant grass seed in Colorado for cool season grasses

Cool-season grasses are the most common types of grass seed planted in Colorado. This includes turf-type tall fescue, Kentucky bluegrass, and perennial ryegrass. While these types can be planted throughout spring and summer, the best time to plant cool-season grass seed is from late March through mid-April. This helps ensure the seedlings have enough time to establish themselves before the warmer summer. 

In areas such as the slopes of the rocky mountains, you can also plant cool-season grass in the fall, as the soil temperature is warm enough for germination at this time. Ensure you plant early enough that your lawn has time to become established before the first frost.

Warm season grasses

Warm-season grasses such as Bermuda, Zoysia, St. Augustine, and Buffalo can be planted in late spring or early summer after the threat of frost has passed. These grasses thrive in warmer climates and need plenty of direct sunlight to grow.

The best time to plant warm-season grass seed in Colorado is from early June through mid-July, as temperatures are warm enough for the seeds to germinate. 

Which type of Grass Seed Grows Best in Colorado?

When to Plant Grass Seed in Colorado

The types of grass seeds that grow best in Colorado are cool-season grasses, including tall fescue, Kentucky bluegrass, and ryegrass. These types of grasses can withstand cold temperatures better than warm-season varieties and will remain green throughout the fall and winter months. 

Additionally, these types are more tolerant to drought than other grass seeds, making them well-suited to the drier conditions of the Colorado climate. You may, however, find that your lawn turns brown and goes dormant during the summer months. 

When selecting grass seed for your Colorado lawn, choose one that is well-suited to your region and has a balance of drought and cold tolerance. Proper selection and timing will ensure you have the best chance for a lush, green lawn! 

Preparing to plant your grass

If you want to create a new lawn, you can either lay sod or plant grass seed, depending on your budget and how quickly you want to establish your lawn. 

There are some steps you should take before planting to get the area ready:

  • Remove garden debris and weeds from the area
  • Test the soil pH range and amend it if necessary
  • Loosen the top inch of soil
  • Apply fertilizer, such as a balanced grass seed starter to the area
  • Plant your grass seed; ensure that they are spread evenly
  • Water, the area, daily until the seeds have germinated


When planting grass seed in Colorado, it’s essential to consider the type of grass and when and how to plant it. The best time for cool-season grasses is from late March through April, while warm-season grasses should be planted in late spring or early summer.

Furthermore, cool-season grasses such as turf-type tall fescue, Kentucky bluegrass, and perennial ryegrass are better suited to the Colorado climate than warm-season varieties. With these tips, you’ll be well on your way to achieving a lush, green lawn in no time. 

Last update on 2024-06-22 / Affiliate links / Images from Amazon Product Advertising API