When to plant Columbine in Summit County, CO
Summit County sits in cold Zone 5a. Plant Columbine June 30–July 21 for the single annual harvest; the September 4 first frost closes the window.
When to Plant Columbine in Summit County, CO
Wild Columbine (Aquilegia canadensis) is a graceful native perennial of eastern North America, producing distinctive nodding flowers with spurred red-and-yellow petals that are irresistible to hummingbirds and native bees in spring. Its blue-green, fernlike foliage remains attractive long after flowering. Garden hybrid columbines (A. x hybrida) extend the color palette to the full spectrum and are equally adaptable. Short-lived by perennial standards (3–4 years per plant), but prolific self-seeders that perpetuate themselves and even hybridize freely in the garden, creating ever-evolving color combinations. An ideal woodland edge and cottage garden plant.
Summit County, Colorado is in USDA Zone 5a. The average last spring frost is June 16 and the first fall frost is September 4, giving you a growing season of approximately 80 days.
At an elevation of 7,005 feet, Summit County receives approximately 17.5 inches of rainfall annually with predominantly loam soil. Summer highs average 81°F, so choose short-season varieties of Columbine to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Columbine successfully. Mulch heavily to conserve soil moisture.
Summit County Soil Profile
Soil Type
Loam
Soil pH
6.0-7.0
Drainage
Well Drained
Columbine Planting Timeline — Summit County, CO
Columbine Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 14 | Apr 14 – Apr 28 |
| Transplant Outdoors | June 30 | Jun 30 – Jul 14 |
| Direct Sow | June 30 | Jun 30 – Jul 21 |
| Bloom | August 25 | Aug 25 – Oct 6 |
Plant 0.1" deep · 12" apart · Rows 18" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | — |
| June | Transplant Outdoors Direct Sow |
| July | Transplant Outdoors Direct Sow |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
Moderate — regular watering
📅 Days to Maturity
70–100 days
🧪 Soil pH
Needs 6–7 · Your soil: N/A
🗺️ USDA Zone
Zone 5a
📆 Growing Season
80 days in Summit County
Growing Tips for Summit County
Start seeds indoors 8–10 weeks before last frost with 4–6 weeks of cold moist stratification first (mix seeds with moist perlite in a bag and refrigerate), or direct-sow outdoors in fall for natural stratification. Transplant to the garden 2–4 weeks after last frost in spring. Prefers cool, moist, well-drained soil with morning sun and afternoon shade, especially in Zones 6+. After bloom, allow seed pods to mature and scatter if you want natural self-seeding; deadhead if you want to prevent spreading. Individual plants are typically short-lived (3–5 years) but colonies persist through prolific self-seeding. Leafminers may create white tunnels in foliage — unsightly but rarely serious. Year 2+ plants flower most profusely.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Columbine in Other Locations
Frequently Asked Questions
When should I plant Columbine in Summit County, CO?
Summit County is in Zone 5a with an average last frost of June 16. Plan your Columbine planting based on this frost date — see the calendar above for exact timing.
What planting zone is Summit County, CO?
Summit County, Colorado is in USDA Hardiness Zone 5a. The average last spring frost is June 16 and first fall frost is September 4.
When should I plant Columbine in Summit County, CO?
In Summit County, CO, plant Columbine after the last frost (around June 16) and before the first frost (around September 4). Best results when soil holds above 50°F.
What growing zone is Summit County, CO for Columbine?
Summit County sits in USDA Zone 5a. Columbine grows reliably in zones 3a through 9a, so it's a good fit here.
Can Columbine grow in Summit County's climate?
Yes — Columbine grows well in Summit County's temperate climate. Summit County averages a 80-day frost-free season, with last frost around June 16 and first frost around September 4.
Your Summit County Garden Planner — Free
A 22-page printable planner built for Summit County (Zone 5a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.