When to plant in Berkley, CO
USDA Zone 6aEverything below — frost dates, hardiness zone, and what to plant when in Berkley, Colorado — is derived from the closest NOAA station with complete climate normals.
In zone 6a, Berkley gardeners can grow many hardy perennials, while the last and first frost still dictate the annual vegetable calendar.
Frost probability
WHEAT RIDGE 2 · 1991–2020The date the last spring and first fall frost occur, by threshold and probability. A 90% date is later in spring — and earlier in fall — than a 10% date; the 50% · 32°F row is what most gardeners plan around. These are Berkley’s own odds, recorded at WHEAT RIDGE 2.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | May 31 | May 16 | May 5 | Sep 13 | Sep 26 | Oct 7 |
| 32°F | May 18 | May 5 | Apr 24 | Sep 20 | Oct 5 | Oct 18 |
| 28°F | May 9 | Apr 25 | Apr 11 | Sep 28 | Oct 14 | Oct 26 |
Download this table as CSV ↓ — every threshold and probability, plus this city’s planting-window dates.
What to plant now
TODAY · JULY 19Full-year planting calendar
Each bar is the exact window to take a planting action in Berkley, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 10 km · complete 32°F normalsWhen stations disagree by more than a few days, that spread is real microclimate variation — elevation, water, urban heat. Judge which station best matches your own yard.
Berkley planting FAQ
When is the last spring frost in Berkley, CO?
On average, the last spring frost in Berkley is around May 5 (50% probability at 32°F, from 1991–2020 NOAA normals). Wait until after this date to set out tender plants like tomatoes and peppers.
When is the first fall frost in Berkley, CO?
In Berkley, the first 32°F freeze of fall lands around October 5 on average. Time your last harvests and any season-extension cover before it.
What hardiness zone is Berkley in?
Berkley is in USDA hardiness zone 6a. In zone 6a, winters are moderate — most common vegetables grow well in season.
How long is the growing season in Berkley?
Berkley has about 153 frost-free days — a moderate growing season — between the average last spring frost (May 5) and first fall frost (October 5).
When should I plant tomatoes in Berkley?
For Berkley, sow tomatoes indoors about March 10–March 24 and move the seedlings out around May 12, after the last spring frost.
Never miss a window in Berkley
An email when it’s time to start seeds, transplant, and sow — timed to Berkley’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Sherrelwood · 4 km
- Welby · 7 km
- Federal Heights · 7 km
- Wheat Ridge · 8 km
- Westminster · 9 km
- Arvada · 11 km
- Northglenn · 12 km
- Denver · 14 km
Frost dates recorded at WHEAT RIDGE 2, 8 km from the city center · 1991–2020 NOAA climate normals · zone from the USDA/PRISM 2023 map. How we compute this.
BlissGarden. "When to Plant in Berkley, CO — Frost Dates & Zone 6a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00058995. Retrieved from https://blissgarden.com/colorado/berkley.