When to plant Columbine in Kent County, DE
Spring Columbine in Kent County goes in April 9–April 30, once nighttime temps stop dipping near freezing.
When to Plant Columbine in Kent County, DE
August in Kent County, Delaware — your action list
Your garden in Kent County, Delaware is working on a schedule, even when you're not. Here's where you should be this August.
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.
Kent County, Delaware is in USDA Zone 7b. The average last spring frost is April 2 and the first fall frost is November 4, giving you a growing season of approximately 216 days.
At an elevation of 128 feet, Kent County receives approximately 47.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88°F, providing good warmth for Columbine during the growing season.
Kent County Soil Profile
Soil Type
Silt Loam
Soil pH
5.8-6.8
Drainage
Well Drained
Columbine Planting Risk Windows
Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.
Soil Compatibility in Kent County
How your county's soil matches Columbine's growing requirements.
Soil pH
Your soil pH (5.8–6.8) overlaps with Columbine's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Kent County is excellent for Columbine — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (3.2%). Annual compost additions will help Columbine.
How to Plant Columbine
Succession Planting Columbine
Sow every 8 weeks. Last sowing by Jul 27 to harvest before frost.
Columbine Water Budget
Monthly Watering Guide for Columbine
Columbine needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Columbine Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 4" | 0" | ❄️ Dormant |
| Feb | — | 2.9" | 0" | ❄️ Dormant |
| Mar | — | 3.5" | 0" | ❄️ Dormant |
| Apr | 4.3" | 4" | 0.3" | 💧 Light watering |
| May | 4.3" | 4.6" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 3.9" | 0.4" | 💧 Light watering |
| Jul | 4.3" | 5.6" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 4.9" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 3.7" | 0.6" | 💧 Light watering |
| Oct | 4.3" | 4" | 0.3" | 💧 Light watering |
| Nov | 4.3" | 3.5" | 0.8" | 💧 Light watering |
| Dec | — | 3.3" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Nov in Kent County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Columbine Heat Requirements (GDD)
What are Growing Degree Days (GDD)?
Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.
Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.
Columbine Planting Timeline — Kent County, DE
Columbine Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 5 | Feb 5 – Feb 19 |
| Transplant Outdoors | April 9 | Apr 9 – Apr 23 |
| Direct Sow | April 9 | Apr 9 – Apr 30 |
| Bloom | May 28 | May 28 – Jul 2 |
Plant 0.1" deep · 12" apart · Rows 18" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | — |
| April | Transplant Outdoors Direct Sow |
| May | Bloom |
| June | Bloom |
| July | Bloom |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
1"/week · Only during dry spells
📅 Days to Maturity
70–100 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 7b
📆 Growing Season
216 days in Kent County
Growing Tips for Columbine in Kent County
Direct sow Columbine outdoors after April 02 in Kent County when soil has warmed and frost danger has passed.
General growing tips
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 Kent County, DE?
Kent County is in Zone 7b with an average last frost of April 2. Plan your Columbine planting based on this frost date — see the calendar above for exact timing.
What planting zone is Kent County, DE?
Kent County, Delaware is in USDA Hardiness Zone 7b. The average last spring frost is April 2 and first fall frost is November 4.
When should I plant Columbine in Kent County, DE?
In Kent County, DE, plant Columbine after the last frost (around April 2) and before the first frost (around November 4). Best results when soil holds above 50°F.
What growing zone is Kent County, DE for Columbine?
Kent County sits in USDA Zone 7b. Columbine grows reliably in zones 3a through 9a, so it's a good fit here.
Can Columbine grow in Kent County's climate?
Yes — Columbine grows well in Kent County's temperate climate. Kent County averages a 216-day frost-free season, with last frost around April 2 and first frost around November 4.
Your Kent County Garden Planner — Free
A 22-page printable planner built for Kent County (Zone 7b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.