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When to Plant Shiso in Otsego County, MI

Shiso (perilla) is a fragrant Japanese herb with large, ruffled leaves in green or purple varieties. It has a unique flavor combining mint, basil, and anise.

Otsego County, Michigan is in USDA Zone 4b. The average last spring frost is May 8 and the first fall frost is October 13, giving you a growing season of approximately 158 days.

At an elevation of 1,278 feet, Otsego County receives approximately 35.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 82ยฐF, so choose short-season varieties of Shiso to ensure they mature before fall.

Otsego County, MI (Zone 4b) Moderate season
158 days
Last Spring Frost May 8
158 growing days
First Fall Frost October 13

Otsego County Soil Profile

Soil Type

Silt Loam

Soil pH

6.1-7.1

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (23 days to spare)
Start indoors: Mar 3 Transplant: May 19 🍅 Harvest: Jul 14 – Sep 8
Recommended (50%) ✓ Fits season (25 days to spare)
Start indoors: Mar 13 Transplant: May 29 🍅 Harvest: Jul 24 – Sep 18
Safe Start (90%) ✓ Fits season (25 days to spare)
Start indoors: Apr 5 Transplant: Jun 21 🍅 Harvest: Aug 16 – Oct 11

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
0.4″/week
Watering frequency 1-2 times/week
Season total 494 gal / 100 sq ft
Shiso needs ~690 GDD — county provides 1,817 GDD Excellent fit

Shiso Planting Timeline โ€” Otsego County, MI

Shiso Planting Calendar

Activity When Date Range
Start Indoors March 13 Mar 13 โ€“ Mar 27
Transplant Outdoors May 29 May 29 โ€“ Jun 12
Direct Sow May 15 May 15 โ€“ Jun 5
Harvest July 24 Jul 24 โ€“ Sep 18

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

Partial Shade (3-6 hours)

Water

Moderate โ€” regular watering

Days to Maturity

50โ€“70 days

Soil pH

5.5 โ€“ 7

USDA Zone

Zone 4b

Growing Season

158 days

Growing Tips for Otsego County

Direct sow after last frost or start indoors. Both green and red varieties are available. Pinch tips to encourage bushiness. Self-sows prolifically; deadhead to control.

Companion Planting

Good Companions

Level Up Your Garden

Frequently Asked Questions

When should I plant Shiso in Otsego County, MI?

Otsego County is in Zone 4b with an average last frost of May 8. Plan your Shiso planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Otsego County, MI?

Otsego County, Michigan is in USDA Hardiness Zone 4b. The average last spring frost is May 8 and first fall frost is October 13.

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Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Otsego County gardeners in Zone 4b organize planting dates, track what's growing, and never miss a planting window.

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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 Otsego County, MI. Local conditions may vary. Last updated: April 2026.