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When to Plant Basil in Leelanau County, MI

Basil is a fragrant warm-season herb essential to Italian and Thai cuisines. It comes in many varieties including sweet, Thai, purple, and lemon types.

Leelanau County, Michigan is in USDA Zone 5b. The average last spring frost is May 5 and the first fall frost is October 22, giving you a growing season of approximately 170 days.

At an elevation of 1,223 feet, Leelanau County receives approximately 41.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88ยฐF, providing good warmth for Basil during the growing season.

Leelanau County, MI (Zone 5b) Moderate season
170 days
Last Spring Frost May 5
170 growing days
First Fall Frost October 22

Leelanau County Soil Profile

Soil Type

Silt Loam

Soil pH

5.8-7.1

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (34 days to spare)
Start indoors: Mar 9 Transplant: May 11 🍅 Harvest: Jul 6 – Sep 7
Recommended (50%) ✓ Fits season (37 days to spare)
Start indoors: Mar 17 Transplant: May 19 🍅 Harvest: Jul 14 – Sep 15
Safe Start (90%) ✓ Fits season (39 days to spare)
Start indoors: Apr 2 Transplant: Jun 4 🍅 Harvest: Jul 30 – Oct 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.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.0″/week
You supply
0.3″/week
Watering frequency Only during dry spells
Season total 416 gal / 100 sq ft
Basil needs ~1,000 GDD — county provides 2,720 GDD Excellent fit

Basil Planting Timeline โ€” Leelanau County, MI

Basil Planting Calendar

Activity When Date Range
Start Indoors March 17 Mar 17 โ€“ Mar 31
Transplant Outdoors May 19 May 19 โ€“ Jun 2
Direct Sow May 12 May 12 โ€“ Jun 2
Harvest July 14 Jul 14 โ€“ Sep 15

Plant 0.5" deep ยท 8" apart ยท Rows 12" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March Start Indoors
April โ€”
May Transplant Outdoors Direct Sow
June Transplant Outdoors Direct Sow
July Harvest
August Harvest
September Harvest
October โ€”
November โ€”
December โ€”

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Moderate โ€” regular watering

Days to Maturity

50โ€“75 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 5b

Growing Season

170 days

Growing Tips for Leelanau County

Start seeds indoors or direct sow after last frost. Pinch flower buds to extend leaf production. Harvest leaves from the top down, cutting just above a leaf pair.

Companion Planting

Good Companions

Avoid Planting Near

  • Rue
  • Sage

Level Up Your Garden

๐ŸŒพ Save Your Own Basil Seeds
Life Cycle Annual
Pollination Self-Pollinating
How to Collect Let flower spikes dry brown on the plant.
Storage Store airtight; viable 5 years at 35ยฐF, under 45% humidity.

Isolate 150 ft between varieties. Different basil species can cross.

Frequently Asked Questions

When should I plant Basil in Leelanau County, MI?

Leelanau County is in Zone 5b with an average last frost of May 5. Plan your Basil planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Leelanau County, MI?

Leelanau County, Michigan is in USDA Hardiness Zone 5b. The average last spring frost is May 5 and first fall frost is October 22.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Leelanau County gardeners in Zone 5b organize planting dates, track what's growing, and never miss a planting window.

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Free download. Plan your entire garden season in minutes.

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