When to plant in Lafayette, CO
USDA Zone 6aLafayette, Colorado frost dates, USDA zone, and a full-year planting calendar, drawn from the nearest NOAA station and tuned to the local season.
Zone 6a means Lafayette sees real winter cold, but a good range of perennials survive; the frost dates above govern when annual vegetables go out.
Frost probability
NORTHGLENN · 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 Lafayette’s own odds, recorded at NORTHGLENN.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | May 26 | May 12 | Apr 30 | Sep 18 | Oct 1 | Oct 14 |
| 32°F | May 14 | May 2 | Apr 18 | Sep 26 | Oct 11 | Oct 24 |
| 28°F | May 5 | Apr 20 | Apr 4 | Oct 7 | Oct 21 | Nov 4 |
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 Lafayette, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 20 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.
Lafayette planting FAQ
When is the last spring frost in Lafayette, CO?
Lafayette's average last spring frost falls near May 2 — the 50% mark at 32°F in the 1991–2020 normals. Hold tender transplants until the risk has passed, then plant out.
When is the first fall frost in Lafayette, CO?
In Lafayette, the first 32°F freeze of fall lands around October 11 on average. Time your last harvests and any season-extension cover before it.
What hardiness zone is Lafayette in?
Lafayette 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 Lafayette?
There are roughly 162 frost-free days in Lafayette (a moderate growing season), running from the average last frost around May 2 to the first fall frost near October 11.
When should I plant tomatoes in Lafayette?
In Lafayette, start tomato seeds indoors around March 7–March 21, then transplant seedlings outdoors around May 9 once the danger of frost has passed.
Never miss a window in Lafayette
An email when it’s time to start seeds, transplant, and sow — timed to Lafayette’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Louisville · 5 km
- Broomfield · 6 km
- Erie · 7 km
- Superior · 9 km
- Gunbarrel · 10 km
- Westminster · 13 km
- Boulder · 13 km
- Northglenn · 14 km
Frost dates recorded at NORTHGLENN, 13 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 Lafayette, CO — Frost Dates & Zone 6a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00055984. Retrieved from https://blissgarden.com/colorado/lafayette.