Blog

When to plant Larkspur in Jackson County, MI

Jackson County gardeners should plant Larkspur between April 1 and April 22 in spring. With Jackson County's Zone 6a climate (last frost April 29), Larkspur needs 60–90 days to mature — plant by July 16 for a full harvest.

When to Plant Larkspur in Jackson County, MI

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.

Jackson County, Michigan 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 1,003 feet, Jackson County receives approximately 37.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Larkspur during the growing season.

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

Jackson County Soil Profile

Soil Type

Silt Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Larkspur Planting Timeline — Jackson County, MI

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 Jackson County

Growing Tips for Jackson 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 Jackson County, MI?

Jackson 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 Jackson County, MI?

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

When should I plant Larkspur in Jackson County, MI?

In Jackson County, MI, plant Larkspur after the last frost (around April 29) and before the first frost (around October 14). Best results when soil holds above 50°F.

What growing zone is Jackson County, MI for Larkspur?

Jackson County sits in USDA Zone 6a. Larkspur grows reliably in zones 2a through 10b, so it's a good fit here.

Can Larkspur grow in Jackson County's climate?

Yes — Larkspur grows well in Jackson County's temperate climate. Jackson County averages a 168-day frost-free season, with last frost around April 29 and first frost around October 14.

🌱

Your Jackson County Garden Planner — Free

A 22-page printable planner built for Jackson 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.

Instant PDF download. No spam, unsubscribe any time.

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

Sources & credits

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