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When to plant Columbine in Boone County, IL

Boone County's climate puts the Columbine spring window between May 7 and May 28. time plantings around the expected last-frost window for best survival.

When to Plant Columbine in Boone County, IL

Boone County, Illinois Zone 5b June

What to do in June

June rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Boone County, Illinois.

Avg. last frost April 23
Avg. first frost October 16
Soil temp (4") 71°F
Watering Low
Pest pressure High
Daylight 15.1 hrs
  1. Time to start columbine inside

    These need a head start before your last frost (April 23). Sow into cells now so you're ready to transplant in a few weeks.

July prep starts now
  • First harvests: columbine

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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.

Boone County, Illinois is in USDA Zone 5b. The average last spring frost is April 23 and the first fall frost is October 16, giving you a growing season of approximately 176 days.

At an elevation of 512 feet, Boone County receives approximately 39.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Columbine to ensure they mature before fall.

Perennial Blooms in Spring Pollinator-friendly Deer-resistant Good for cutting
Boone County, IL (Zone 5b) Moderate season
176 days
Last Spring Frost April 23
176 growing days
First Fall Frost October 16

Boone County Soil Profile

Soil Type

Silt Loam

Soil pH

6-6.8

Drainage

Well Drained

Columbine Planting Risk Windows

Early Start (70% safe) ✓ Fits season (65 days to spare)
Start indoors: Feb 13 Transplant: May 1 🌸 Bloom: Jun 26 – Aug 7
Recommended (50%) ✓ Fits season (64 days to spare)
Start indoors: Feb 19 Transplant: May 7 🌸 Bloom: Jul 2 – Aug 13
Safe Start (90%) ✓ Fits season (61 days to spare)
Start indoors: Mar 8 Transplant: May 24 🌸 Bloom: Jul 19 – Aug 30

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 Boone County

How your county's soil matches Columbine's growing requirements.

Soil pH

Your soil pH (6.0–6.8) is within Columbine's preferred range (6.0–7.0).

Soil Texture

The silt loam soil in Boone County is excellent for Columbine — good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for Columbine.

Organic Matter

Organic matter is moderate (3.8%). Annual compost additions will help Columbine.

How to Plant Columbine

0.1"
Planting Depth
12"
Between Plants
18"
Between Rows

Succession Planting Columbine

2
successive plantings in your 176-day season

Sow every 8 weeks. Last sowing by Jul 08 to harvest before frost.

Columbine Water Budget

Plant needs
1.0″/week
Rainfall provides
1.0″/week
You supply
0.4″/week
Watering frequency 1-2 times/week
Season total 654 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

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 1.6" 0" ❄️ Dormant
Feb 1.5" 0" ❄️ Dormant
Mar 2.7" 0" ❄️ Dormant
Apr 4.3" 3.4" 0.9" 💧 Light watering
May 4.3" 4.1" 0.2" 💧 Light watering
Jun 4.3" 5.7" 0" ✅ Rainfall sufficient
Jul 4.3" 4.9" 0" ✅ Rainfall sufficient
Aug 4.3" 3.8" 0.5" 💧 Light watering
Sep 4.3" 3.5" 0.8" 💧 Light watering
Oct 4.3" 3.5" 0.8" 💧 Light watering
Nov 2.9" 0" ❄️ Dormant
Dec 2.3" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Boone 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 needs ~1,041 GDD — county provides 2,156 GDD Excellent fit

Columbine Planting Timeline — Boone County, IL

Columbine Planting Calendar

Activity When Date Range
Start Indoors February 19 Feb 19 – Mar 5
Transplant Outdoors May 7 May 7 – May 21
Direct Sow May 7 May 7 – May 28
Bloom July 2 Jul 2 – Aug 13

Plant 0.1" deep · 12" apart · Rows 18" apart

Month-by-Month Timeline

MonthActivities
January
February Start Indoors
March Start Indoors
April
May Transplant Outdoors Direct Sow
June
July Bloom
August Bloom
September
October
November
December

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · 1-2 times/week

📅 Days to Maturity

70–100 days

🧪 Soil pH

Needs 6–7 · Your soil: ideal

🗺️ USDA Zone

Zone 5b

📆 Growing Season

176 days in Boone County

Growing Tips for Columbine in Boone County

Direct sow Columbine outdoors after April 23 in Boone 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 →

Frequently Asked Questions

When should I plant Columbine in Boone County, IL?

Boone County is in Zone 5b with an average last frost of April 23. Plan your Columbine planting based on this frost date — see the calendar above for exact timing.

What planting zone is Boone County, IL?

Boone County, Illinois is in USDA Hardiness Zone 5b. The average last spring frost is April 23 and first fall frost is October 16.

When should I plant Columbine in Boone County, IL?

In Boone County, IL, plant Columbine after the last frost (around April 23) and before the first frost (around October 16). Best results when soil holds above 50°F.

What growing zone is Boone County, IL for Columbine?

Boone County sits in USDA Zone 5b. Columbine grows reliably in zones 3a through 9a, so it's a good fit here.

Can Columbine grow in Boone County's climate?

Yes — Columbine grows well in Boone County's temperate climate. Boone County averages a 176-day frost-free season, with last frost around April 23 and first frost around October 16.

🌱

Your Boone County Garden Planner — Free

A 22-page printable planner built for Boone County (Zone 5b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Boone County, IL. Local conditions may vary. Last updated: June 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.