When to Plant Larkspur in Hardin 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.
Hardin County, Ohio is in USDA Zone 6a. The average last spring frost is April 26 and the first fall frost is October 20, giving you a growing season of approximately 177 days.
At an elevation of 935 feet, Hardin County receives approximately 30.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Larkspur during the growing season.
Hardin County Soil Profile
Soil Type
Silt Loam
Soil pH
6.0-7.0
Drainage
Well Drained
Larkspur Planting Timeline — Hardin County, OH
Larkspur Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | March 29 | Mar 29 – Apr 19 |
| Bloom | June 7 | Jun 7 – Aug 2 |
Plant 0.1" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Direct Sow |
| 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
177 days in Hardin County
Growing Tips for Hardin 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 →
Larkspur in Other Locations
Frequently Asked Questions
When should I plant Larkspur in Hardin County, OH?
Hardin County is in Zone 6a with an average last frost of April 26. Plan your Larkspur planting based on this frost date — see the calendar above for exact timing.
What planting zone is Hardin County, OH?
Hardin County, Ohio is in USDA Hardiness Zone 6a. The average last spring frost is April 26 and first fall frost is October 20.
Your Hardin County Garden Planner — Free
A 22-page printable planner built for Hardin 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.