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When to Plant Larkspur in Williams County, OH

Larkspur (Consolida ajacis) is a cool-season annual that produces tall, delicate spires of blue, purple, pink, and white flowers reminiscent of its perennial cousin, delphinium. Direct-sown into cold soil or fall-sown in mild-winter climates, it blooms in spring before going to seed as summer heat arrives. An excellent cut flower and cottage-garden staple.

Williams County, Ohio is in USDA Zone 6a. The average last spring frost is April 29 and the first fall frost is October 14, giving you a growing season of approximately 168 days.

At an elevation of 1,057 feet, Williams County receives approximately 39.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Larkspur during the growing season.

Annual Blooms in Spring Pollinator-friendly Deer-resistant Good for cutting
Williams County, OH (Zone 6a) Moderate season
168 days
Last Spring Frost April 29
168 growing days
First Fall Frost October 14

Williams County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-6.9

Drainage

Well Drained

Monthly Watering Guide for Larkspur

Larkspur needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Larkspur Needs Rainfall You Supplement Action
Jan 1.5" 0" ❄️ Dormant
Feb 1.6" 0" ❄️ Dormant
Mar 2.5" 0" ❄️ Dormant
Apr 4.3" 4.1" 0.2" 💧 Light watering
May 4.3" 4.6" 0" ✅ Rainfall sufficient
Jun 4.3" 4.8" 0" ✅ Rainfall sufficient
Jul 4.3" 4.1" 0.2" 💧 Light watering
Aug 4.3" 4.6" 0" ✅ Rainfall sufficient
Sep 4.3" 3.4" 0.9" 💧 Light watering
Oct 4.3" 3.1" 1.2" 💧 Light watering
Nov 3.1" 0" ❄️ Dormant
Dec 2.1" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Williams County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Larkspur Planting Timeline — Williams County, OH

Larkspur Planting Calendar

Activity When Date Range
Direct Sow April 1 Apr 1 – Apr 22
Bloom June 10 Jun 10 – Aug 5

Plant 0.1" deep · 8" apart · Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Low — drought tolerant

📅 Days to Maturity

60–90 days

🧪 Soil pH

Needs 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 6a

📆 Growing Season

168 days in Williams County

Growing Tips for Williams County

Larkspur does not transplant well — direct-sow only. In cold climates (zones 2–6), sow directly in early spring as soon as soil can be worked, 4–6 weeks before last frost; cold soil improves germination. In zones 7–10, fall-sow 8–10 weeks before first frost for spring bloom. Press seeds lightly into soil; they need darkness to germinate — cover with 1/8–1/4 inch of soil. Thin to 6–12 inches to prevent powdery mildew. Allow seed pods to mature and self-sow for naturalized colonies. All parts are toxic if ingested.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Larkspur in Williams County, OH?

Williams County is in Zone 6a with an average last frost of April 29. Plan your Larkspur planting based on this frost date — see the calendar above for exact timing.

What planting zone is Williams County, OH?

Williams County, Ohio is in USDA Hardiness Zone 6a. The average last spring frost is April 29 and first fall frost is October 14.

🌱

Your Williams County Garden Planner — Free

A 22-page printable planner built for Williams County (Zone 6a). 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 Williams County, OH. Local conditions may vary. Last updated: August 2026.

Sources & credits

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