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When to Plant Columbine in King County, TX

King County, Texas Zone 8a June

June in the garden — King County, Texas

Your garden in King County, Texas is working on a schedule, even when you're not. Here's where you should be this June.

Avg. last frost March 31
Avg. first frost November 7
Soil temp (4") 71°F
Watering High
Pest pressure High
Daylight 14.2 hrs
  1. It's harvest week for columbine

    Morning harvests are best — cooler temperatures mean crisper produce and longer fridge life.

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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.

King County, Texas is in USDA Zone 8a. The average last spring frost is March 31 and the first fall frost is November 7, giving you a growing season of approximately 221 days.

At an elevation of 3,170 feet, King County receives approximately 60.2 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 99°F, so Columbine may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Columbine will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Columbine root diseases.

Perennial Blooms in Spring Pollinator-friendly Deer-resistant Good for cutting
King County, TX (Zone 8a) Long season
221 days
Last Spring Frost March 31
221 growing days
First Fall Frost November 7

King County Soil Profile

Soil Type

Sandy Loam

Soil pH

7.8-8.4

Drainage

Well Drained

Columbine Planting Risk Windows

Early Start (70% safe) ✓ Fits season (145 days to spare)
Start indoors: Jan 26 Transplant: Mar 23 🌸 Bloom: May 11 – Jun 8
Recommended (50%) ✓ Fits season (144 days to spare)
Start indoors: Feb 3 Transplant: Mar 31 🌸 Bloom: May 19 – Jun 16
Safe Start (90%) ✓ Fits season (144 days to spare)
Start indoors: Feb 18 Transplant: Apr 15 🌸 Bloom: Jun 3 – Jul 1

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 King County

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

Soil pH

Your soil pH (7.8–8.4) is more alkaline than Columbine prefers (6.0–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

Sandy soil in King County warms quickly in spring but drains fast. Columbine will need more frequent watering and regular compost additions to retain nutrients.

Organic Matter

Organic matter is low (1.1%). Add 2-3 inches of compost before planting Columbine.

How to Plant Columbine

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

Succession Planting Columbine

3
successive plantings in your 221-day season

Sow every 8 weeks. Last sowing by Jul 30 to harvest before frost.

Columbine Water Budget

Plant needs
1.0″/week
Rainfall provides
1.1″/week
Watering frequency Natural rainfall sufficient
Season total 0 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 4.7" 0" ❄️ Dormant
Feb 3.2" 0" ❄️ Dormant
Mar 4.3" 3.9" 0.4" 💧 Light watering
Apr 4.3" 2.3" 2" 💧 Light watering
May 4.3" 1.5" 2.8" 🚿 Regular watering
Jun 4.3" 2.2" 2.1" 💧 Light watering
Jul 4.3" 10.4" 0" ✅ Rainfall sufficient
Aug 4.3" 11.5" 0" ✅ Rainfall sufficient
Sep 4.3" 8.1" 0" ✅ Rainfall sufficient
Oct 4.3" 5.7" 0" ✅ Rainfall sufficient
Nov 4.3" 3" 1.3" 💧 Light watering
Dec 3.7" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in King 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 ~2,061 GDD — county provides 5,359 GDD Excellent fit

Columbine Planting Timeline — King County, TX

Columbine Planting Calendar

Activity When Date Range
Start Indoors February 3 Feb 3 – Feb 17
Transplant Outdoors March 31 Mar 31 – Apr 14
Direct Sow March 31 Mar 31 – Apr 21
Bloom May 19 May 19 – Jun 16

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · Natural rainfall sufficient

📅 Days to Maturity

70–100 days

🧪 Soil pH

Needs 6–7 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 8a

📆 Growing Season

221 days in King County

Growing Tips for Columbine in King County

Direct sow Columbine outdoors after March 31 in King County when soil has warmed and frost danger has passed.

Sandy soil in King County dries quickly — mulch Columbine with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

With summer highs reaching 99°F in King County, provide afternoon shade for Columbine and water deeply in the morning.

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 King County, TX?

King County is in Zone 8a with an average last frost of March 31. Plan your Columbine planting based on this frost date — see the calendar above for exact timing.

What planting zone is King County, TX?

King County, Texas is in USDA Hardiness Zone 8a. The average last spring frost is March 31 and first fall frost is November 7.

🌱

Your King County Garden Planner — Free

A 22-page printable planner built for King County (Zone 8a). 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 King County, TX. 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.