Red Feather Lakes, CO 82059 planting calendar
- USDA zone
- 5b−15 to −10 °F
- Last frost
- May 31avg, 32°F
- First frost
- Sep 19avg, 32°F
- Growing season
- 110days
Red Feather Lakes, Colorado is in USDA plant hardiness zone 5b. Its average last spring frost is around May 31 and the first fall frost around September 19, giving a growing season of about 110 days (NOAA 1991–2020 normals, 32°F, median). Start tender crops like tomatoes and peppers indoors weeks before the last frost and set them out afterward; sow hardy crops such as peas, spinach, and lettuce before it. The planner below turns those frost dates into a printable per-crop planting calendar.
Red Feather Lakes planting calendar
Each crop's windows are counted from Red Feather Lakes's average frost dates. hatched = start seeds indoors, solid green = plant out, teal = a fall sowing, and the terracotta dot marks the estimated first harvest. Ranges are extension-guide planning guidance, not guarantees.
- Start indoors
- Plant out
- Fall sowing
- First harvest
| Crop | Frost tolerance | Start indoors | Plant out | First harvest | Fall planting |
|---|---|---|---|---|---|
| Tomato | Tender | Apr 5 – Apr 19 | Jun 7 – Jun 14 | Aug 6 – Aug 26 | — |
| Pepper | Very tender | Mar 22 – Apr 5 | Jun 14 – Jun 21 | Aug 13 – Sep 12 | — |
| Cucumber | Tender | May 3 – May 10 | Jun 7 – Jun 14 | Jul 27 – Aug 16 | — |
| Summer squash / zucchini | Tender | — | Jun 7 – Jun 14 | Jul 22 – Aug 6 | — |
| Bush bean | Tender | — | Jun 7 – Jun 14 | Jul 27 – Aug 6 | Jul 21 – Jul 31 |
| Sweet corn | Tender | — | May 31 – Jun 14 | Jul 30 – Aug 29 | — |
| Basil | Very tender | Apr 19 – May 3 | Jun 7 – Jun 14 | Jul 7 – Jul 22 | — |
| Lettuce | Half-hardy | Apr 19 – May 3 | May 3 – May 17 | Jun 17 – Jul 2 | Jul 7 – Jul 22 |
| Pea | Hardy | — | Apr 19 – May 3 | Jun 13 – Jun 28 | Jun 27 – Jul 12 |
| Spinach | Hardy | — | Apr 19 – May 3 | May 29 – Jun 8 | Jul 17 – Jul 27 |
| Carrot | Half-hardy | — | May 10 – May 17 | Jul 9 – Jul 29 | Jun 17 – Jul 7 |
| Broccoli | Half-hardy | Apr 5 – Apr 19 | May 3 – May 17 | Jun 27 – Jul 17 | Jun 22 – Jul 12 |
Data: NOAA NCEI U.S. Climate Normals 1991–2020 (public domain) and USDA Plant Hardiness Zone Map 2023. Planting windows synthesized from U.S. Cooperative Extension guides.
Frost & freeze dates
From NOAA's 1991–2020 Climate Normals at station USC00058690. The median (p50) is the average date; the 90%-safe column is the date the freeze has passed in about 9 years out of 10 (p10 for spring, p90 for fall) — the conservative date to plant after or harvest before.
| Threshold | Last spring — avg | Last spring — 90%-safe | First fall — avg | First fall — 90%-safe | Season (days) |
|---|---|---|---|---|---|
| 36°F | Jun 14 | Jun 30 | Sep 8 | Sep 22 | 87 |
| 32°F (freeze) | May 31 | Jun 15 | Sep 19 | Oct 1 | 110 |
| 28°F | May 16 | May 31 | Sep 29 | Oct 12 | 134 |
| 24°F | May 2 | May 17 | Oct 8 | Oct 25 | 157 |
32°F is the standard "freeze" line that damages tender crops; lighter 36°F frost can nip the most cold-sensitive plants, while hardy crops shrug off light frost down toward 28°F. Use the threshold that matches what you are protecting.
Growing degree days
Growing degree days (GDD) accumulate warmth above a base temperature over the year — a better predictor of crop development than the calendar alone. Warm-season crops need a long, warm GDD total; a short, cool GDD total favors greens and brassicas.
| Model | °F·days | Used for |
|---|---|---|
| Base 50°F (warm-season) | 1,553 | standard warm-season base (tomato, corn, beans) |
| Base 40°F (cool-season) | 3,276 | cool-season crops (brassicas, greens) |
Hardiness zone 5b
Red Feather Lakes sits in USDA plant hardiness zone 5b on the 2023 map — meaning its average annual extreme minimum winter temperature is about −15 to −10 °F. That number tells you which perennials, shrubs, and trees reliably survive an average winter here; it does not set your planting dates, which come from the frost calendar above.
Explore more places in zone 5b, or see all USDA hardiness zones.
Frequently asked questions
- What USDA hardiness zone is Red Feather Lakes?
- Red Feather Lakes, Colorado is in USDA plant hardiness zone 5b on the 2023 map (average annual extreme minimum temperature −15 to −10 °F) — from the USDA Plant Hardiness Zone Map 2023, matched to this location's ZIP. See the methodology page for sources.
- When is the last frost in Red Feather Lakes?
- The average (median) last spring frost at 32°F is around May 31, from NOAA's 1991–2020 climate normals at the nearest reporting station. Roughly one year in ten the last frost is as late as June 15, so wait until then before setting out frost-tender plants if you want to be safe.
- When is the first fall frost in Red Feather Lakes?
- The average first fall frost at 32°F is around September 19. That leaves a growing season of about 110 days between the average last spring and first fall frosts.
- When should I start tomatoes in Red Feather Lakes?
- Start tomato seeds indoors about Apr 5 – Apr 19 and transplant them outside about Jun 7 – Jun 14, once the danger of frost has passed. Estimated first harvest is around Aug 6 – Aug 26.
- How long is the growing season in Red Feather Lakes?
- About 110 days at the 32°F threshold (NOAA 1991–2020, median) — the span between the average last spring frost (~May 31) and the average first fall frost (~September 19). Cold-hardy crops extend usable time at both ends; frost-tender crops fit inside it.
Sources & method
Frost, freeze, growing-season, and growing-degree-day figures are NOAA NCEI U.S. Climate Normals 1991–2020 for station USC00058690 (Virginia Dale 7 Ene, 10.3 km away). The hardiness zone is the USDA Plant Hardiness Zone Map 2023, matched to this location's ZIP. Planting windows are computed by counting from the average last and first frost using per-crop offsets synthesized from U.S. Cooperative Extension guides — the full method and citations are on the methodology page.