Frost dates for 80130Littleton, CO
The average last spring frost in Littleton is May 5 and the average first fall frost is October 8, giving a typical growing season of about 154 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 5
- Average first fall frost
- Oct 8
- Growing season
- 154 days
Safer after May 17 (1-in-10 risk)
Possible by Sep 25 (1-in-10 risk)
Last frost typically in 191 days
Frost risk by date
NOAA reports frost dates as probabilities. The middle date is the average (a 50% chance). For spring, the 10% date is a safer planting date: frost after it happens in about 1 year in 10. Light frost (36°F) can damage tender plants; a hard freeze (28°F) kills most annuals.
| Temperature | Last spring: 90% / 50% / 10% chance | First fall: 10% / 50% / 90% chance | Growing season (50%) | Years with at least one |
|---|---|---|---|---|
| Light frost (36°F) | May 3 · May 15 · May 30 | Sep 17 · Oct 1 · Oct 12 | 136 days | 100% |
| Frost / freeze (32°F) | Apr 24 · May 5 · May 17 | Sep 25 · Oct 8 · Oct 20 | 154 days | 100% |
| Hard freeze (28°F) | Apr 10 · Apr 25 · May 9 | Oct 4 · Oct 17 · Oct 28 | 172 days | 100% |
Planting calendar for Littleton
Planting windows from the University of Maryland Extension calendar, shifted to your average frost dates. Use them as a starting point and adjust for seed packet instructions and local conditions.
| Crop | Task | Window |
|---|---|---|
| Tomatoes | Start seeds indoors | Apr 4 – Jun 10 |
| Tomatoes | Transplant outdoors | May 21 – Jun 18 |
| Peppers | Start seeds indoors | Apr 4 – May 5 |
| Peppers | Transplant outdoors | Jun 4 – Jul 5 |
| Eggplant | Start seeds indoors | Apr 21 – May 20 |
| Eggplant | Transplant outdoors | Jun 4 – Jul 5 |
| Cucumbers | Sow outdoors | Jun 4 – Jun 28 |
| Summer squash | Sow outdoors | May 21 – Jul 5 |
| Winter squash & pumpkins | Sow outdoors | Jun 4 – Jul 5 |
| Snap beans | Sow outdoors | May 21 – Jul 21 |
| Sweet corn | Sow outdoors | May 21 – Jun 18 |
| Watermelon & cantaloupe | Sow outdoors | Jun 4 – Jul 5 |
| Okra | Sow outdoors | May 28 – Jun 20 |
| Peas | Sow outdoors (spring) | Apr 4 – May 20 |
| Potatoes | Plant outdoors (spring) | Apr 4 – Jun 4 |
| Onions | Start seeds indoors (spring) | Feb 21 – Mar 20 |
| Onions | Transplant outdoors (spring) | Apr 21 – May 20 |
| Broccoli | Start seeds indoors (spring) | Mar 17 – Apr 20 |
| Broccoli | Transplant outdoors (spring) | Apr 21 – May 20 |
| Broccoli | Start seeds indoors (fall) | Jun 8 – Jun 18 |
| Broccoli | Transplant outdoors (fall) | Jul 8 – Jul 19 |
| Cabbage | Start seeds indoors (spring) | Mar 7 – Apr 4 |
| Cabbage | Transplant outdoors (spring) | Apr 4 – May 5 |
| Cabbage | Start seeds indoors (fall) | May 29 – Jun 28 |
| Cabbage | Transplant outdoors (fall) | Jun 28 – Jul 29 |
| Leaf lettuce | Sow outdoors (spring) | Apr 4 – Jun 20 |
| Leaf lettuce | Sow outdoors (fall) | Jun 28 – Aug 14 |
| Spinach | Sow outdoors (spring) | Mar 28 – May 11 |
| Spinach | Sow outdoors (fall) | Jul 15 – Aug 19 |
| Radishes | Sow outdoors (spring) | Apr 4 – May 25 |
| Radishes | Sow outdoors (fall) | Jun 28 – Aug 29 |
| Kale | Sow outdoors (spring) | Apr 21 – May 11 |
| Kale | Sow outdoors (fall) | Jun 21 – Jul 29 |
| Carrots | Sow outdoors (spring) | May 5 – Jun 20 |
| Carrots | Sow outdoors (fall) | May 29 – Jul 14 |
| Garlic | Plant outdoors (fall) | Sep 28 – Oct 29 |
Where these dates come from
ZIP code 80130 is matched to the NOAA station Denver Centennial Ap, CO, 7 km away, at 5,883 ft elevation (50 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Denver Centennial Ap, CO (used) | 5,883 ft | May 5 | Oct 8 |
| Cherry Creek Dam, CO | 5,647 ft | May 7 | Oct 8 |
| Castle Rock, CO | 6,185 ft | May 9 | Oct 2 |
| Parker, CO | 5,904 ft | May 9 | Oct 3 |
Frost dates near Littleton
- Lone Tree, CO 80124 · last May 5, first Oct 8
- Littleton, CO 80126 · last May 5, first Oct 8
- Englewood, CO 80112 · last May 5, first Oct 8
- Parker, CO 80134 · last May 9, first Oct 2
- Louviers, CO 80131 · last May 8, first Oct 3
- Denver, CO 80237 · last May 2, first Oct 11
- Castle Rock, CO 80108 · last May 9, first Oct 2
- Aurora, CO 80015 · last May 5, first Oct 8
Frequently asked questions
- When is the last frost in Littleton, CO?
- For ZIP code 80130, the average last spring frost (32°F) is May 5, based on NOAA 1991-2020 climate normals for the Denver Centennial Ap, CO weather station. There is a 1-in-10 chance of a frost after May 17.
- When is the first frost in Littleton, CO?
- The average first fall frost (32°F) is October 8. There is a 1-in-10 chance of frost by September 25, so tender plants are at risk from that point on.
- How long is the growing season in 80130?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 154 days long.
- Are these frost dates a forecast?
- No. They are 30-year averages and probabilities from NOAA weather station records. Use them to plan, then watch your local forecast before planting tender crops or leaving them uncovered.