When to Plant Shallot in Colorado
Start Seeds Indoors
Transplant outdoors:
State
Colorado
USDA Zones
4a, 4b, 5a, 5b, 6a, 6b, 7a
Avg Last Frost
Tuesday, April 20, 2027
Cities Covered
397
Colorado Planting Schedule by Zone
Colorado spans 7 zones — find yours below for the most accurate dates.
| Zone | Last Frost | Start Indoors | Transplant |
|---|---|---|---|
| 4a | Saturday, May 15, 2027 | — | — |
| 4b | Wednesday, May 5, 2027 | — | — |
| 5a | Monday, May 10, 2027 | — | — |
| 5b | Sunday, April 25, 2027 | — | — |
| 6a | Tuesday, April 20, 2027 | — | — |
| 6b | Thursday, April 15, 2027 | — | — |
| 7a | Saturday, April 10, 2027 | — | — |
Dates based on average last frost. Check your local forecast before planting.
🌿 About Shallot
Growing Shallot in Colorado: Complete Guide
Shallot (Allium cepa var. aggregatum) is a warm-season crop that needs a head start indoors before Colorado's last frost. Depending on your zone, Colorado gardeners start seeds indoors between September 10, 2026 (Zone 4a) and October 15, 2026 (Zone 7a), then move transplants outside once their zone's last frost has passed — the zone table above has your exact dates.
Because Colorado stretches across 7 USDA hardiness zones (4a, 4b, 5a, 5b, 6a, 6b, 7a), planting windows can shift by as much as six to eight weeks from one end of the state to the other. Gardeners in the warmer southern zones can start earlier, while those in cooler northern zones should wait until the zone table above shows their last frost has passed.
With 90 days to maturity, Shallot needs the indoor head start that Colorado's growing season requires. Starting indoors ensures you have strong transplants ready the moment outdoor conditions are right.
Shallot requires full sun and regular moisture. Mountain-state gardens contend with short seasons and intense UV at elevation — cold nights can persist well into June at higher altitudes.
For the most precise planting dates tailored to your exact location, enter your ZIP code on our planting calendar or use the zone table above to find the schedule for your area of Colorado.
Frequently Asked Questions
When should I plant Shallot in Colorado?
In Colorado, start Shallot seeds indoors around null and transplant outdoors around null after your last frost. Colorado spans zones 4a–7a, so dates shift by 1–4 weeks depending on where you live.
What is the last frost date in Colorado?
Colorado spans 7 USDA zones (4a, 4b, 5a, 5b, 6a, 6b, 7a), so last frost dates vary by region. Hartsel, Gunnison, Craig (4a) sees frost until around Saturday, May 15, 2027, while Cortez, Mesa Verde National Park, Towaoc (7a) is frost-free much earlier.
How long does Shallot take to grow in Colorado?
Shallot takes about 90 days from transplant (or direct sow) to harvest. Starting seeds indoors in Colorado gives you a head start so plants are ready to go out after the last frost.
What USDA zones does Colorado cover for Shallot?
Colorado includes zones 4a, 4b, 5a, 5b, 6a, 6b, 7a. Shallot grows well across all of these zones with adjusted timing — use the zone table above to find the right dates for your part of the state.
When to Plant Shallot by City in Colorado
Dates are based on each city's USDA zone and average last frost.
| City | Zone | Last Frost | Start Indoors | Transplant |
|---|---|---|---|---|
| Agate | 5b | Sunday, April 25, 2027 | — | — |
| Aguilar | 6a | Tuesday, April 20, 2027 | — | — |
| Akron | 5b | Sunday, April 25, 2027 | — | — |
| Alamosa | 4b | Wednesday, May 5, 2027 | — | — |
| Allenspark | 5b | Sunday, April 25, 2027 | — | — |
| Alma | 5a | Monday, May 10, 2027 | — | — |
| Almont | 5a | Monday, May 10, 2027 | — | — |
| Amherst | 5b | Sunday, April 25, 2027 | — | — |
| Anton | 5b | Sunday, April 25, 2027 | — | — |
| Antonito | 5b | Sunday, April 25, 2027 | — | — |
| Arapahoe | 6a | Tuesday, April 20, 2027 | — | — |
| Arboles | 6b | Thursday, April 15, 2027 | — | — |
| Arlington | 5b | Sunday, April 25, 2027 | — | — |
| Arriba | 5b | Sunday, April 25, 2027 | — | — |
| Arvada | 6a | Tuesday, April 20, 2027 | — | — |
| Aspen | 5a | Monday, May 10, 2027 | — | — |
| Atwood | 5b | Sunday, April 25, 2027 | — | — |
| Ault | 5a | Monday, May 10, 2027 | — | — |
| Aurora | 6a | Tuesday, April 20, 2027 | — | — |
| Austin | 6b | Thursday, April 15, 2027 | — | — |
| Avon | 6a | Tuesday, April 20, 2027 | — | — |
| Avondale | 6a | Tuesday, April 20, 2027 | — | — |
| Bailey | 5b | Sunday, April 25, 2027 | — | — |
| Basalt | 6a | Tuesday, April 20, 2027 | — | — |
| Battlement Mesa | 6b | Thursday, April 15, 2027 | — | — |
| Bayfield | 6a | Tuesday, April 20, 2027 | — | — |
| Bedrock | 6b | Thursday, April 15, 2027 | — | — |
| Bellvue | 5b | Sunday, April 25, 2027 | — | — |
| Bennett | 6a | Tuesday, April 20, 2027 | — | — |
| Berthoud | 5b | Sunday, April 25, 2027 | — | — |
| Bethune | 6a | Tuesday, April 20, 2027 | — | — |
| Beulah | 6a | Tuesday, April 20, 2027 | — | — |
| Black Hawk | 5b | Sunday, April 25, 2027 | — | — |
| Blanca | 5a | Monday, May 10, 2027 | — | — |
| Boncarbo | 6a | Tuesday, April 20, 2027 | — | — |
| Bond | 5b | Sunday, April 25, 2027 | — | — |
| Boone | 6a | Tuesday, April 20, 2027 | — | — |
| Boulder | 6a | Tuesday, April 20, 2027 | — | — |
| Branson | 6a | Tuesday, April 20, 2027 | — | — |
| Breckenridge | 5a | Monday, May 10, 2027 | — | — |
| Briggsdale | 5a | Monday, May 10, 2027 | — | — |
| Brighton | 5b | Sunday, April 25, 2027 | — | — |
| Broomfield | 6a | Tuesday, April 20, 2027 | — | — |
| Brush | 5b | Sunday, April 25, 2027 | — | — |
| Buena Vista | 5b | Sunday, April 25, 2027 | — | — |
| Buffalo Creek | 5b | Sunday, April 25, 2027 | — | — |
| Burlington | 6a | Tuesday, April 20, 2027 | — | — |
| Burns | 5b | Sunday, April 25, 2027 | — | — |
| Byers | 5b | Sunday, April 25, 2027 | — | — |
| Cahone | 6b | Thursday, April 15, 2027 | — | — |
| Calhan | 5b | Sunday, April 25, 2027 | — | — |
| Campo | 6b | Thursday, April 15, 2027 | — | — |
| Canon City | 6a | Tuesday, April 20, 2027 | — | — |
| Capulin | 5a | Monday, May 10, 2027 | — | — |
| Carbondale | 6a | Tuesday, April 20, 2027 | — | — |
| Carr | 5b | Sunday, April 25, 2027 | — | — |
| Cascade | 5b | Sunday, April 25, 2027 | — | — |
| Castle Rock | 5b | Sunday, April 25, 2027 | — | — |
| Cedaredge | 5b | Sunday, April 25, 2027 | — | — |
| Center | 5a | Monday, May 10, 2027 | — | — |
Showing 60 of 397 cities. Enter your ZIP on the planting calendar for your exact dates.