Blog

When to Plant Shiso in Newaygo 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.

Newaygo County, Michigan is in USDA Zone 5b. The average last spring frost is May 16 and the first fall frost is October 5, giving you a growing season of approximately 142 days.

At an elevation of 592 feet, Newaygo County receives approximately 38.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87ยฐF, providing good warmth for Shiso during the growing season.

Newaygo County, MI (Zone 5b) Short season
142 days
Last Spring Frost May 16
142 growing days
First Fall Frost October 5

Newaygo County Soil Profile

Soil Type

Silt Loam

Soil pH

5.8-6.9

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (19 days to spare)
Start indoors: Mar 20 Transplant: May 22 🍅 Harvest: Jul 17 – Sep 11
Recommended (50%) ✓ Fits season (16 days to spare)
Start indoors: Mar 28 Transplant: May 30 🍅 Harvest: Jul 25 – Sep 19
Safe Start (90%) ✓ Fits season (20 days to spare)
Start indoors: Apr 10 Transplant: Jun 12 🍅 Harvest: Aug 7 – Oct 2

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.

Soil Compatibility in Newaygo County

How your county's soil matches Shiso's growing requirements.

Soil pH

Your soil pH (5.8โ€“6.9) is within Shiso's preferred range (5.5โ€“7.0).

Soil Texture

The silt loam soil in Newaygo County is excellent for Shiso โ€” good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for Shiso.

Organic Matter

Organic matter is excellent (4.9%) โ€” Shiso will thrive.

How to Plant Shiso

0.5"
Planting Depth
8"
Between Plants
12"
Between Rows

Succession Planting Shiso

3
successive plantings in your 142-day season

Sow every 5.7 weeks. Last sowing by Jul 27 to harvest before frost.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.1″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 215 gal / 100 sq ft

Monthly Watering Guide for Shiso

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

Month Shiso Needs Rainfall You Supplement Action
Jan โ€” 1.5" 0" โ„๏ธ Dormant
Feb โ€” 1.9" 0" โ„๏ธ Dormant
Mar โ€” 2.6" 0" โ„๏ธ Dormant
Apr โ€” 3.3" 0" โ„๏ธ Dormant
May 4.3" 4.5" 0" โœ… Rainfall sufficient
Jun 4.3" 4.3" 0" โœ… Rainfall sufficient
Jul 4.3" 4.9" 0" โœ… Rainfall sufficient
Aug 4.3" 3.8" 0.5" ๐Ÿ’ง Light watering
Sep 4.3" 3.2" 1.1" ๐Ÿ’ง Light watering
Oct 4.3" 3.2" 1.1" ๐Ÿ’ง Light watering
Nov โ€” 2.6" 0" โ„๏ธ Dormant
Dec โ€” 2.4" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Mayโ€“Oct in Newaygo County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Shiso Heat Requirements (GDD)

What are Growing Degree Days (GDD)?

Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" โ€” every day above 50ยฐF deposits warmth that helps your plants grow.

Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.

Shiso needs ~915 GDD — county provides 2,165 GDD Excellent fit

Shiso Planting Timeline โ€” Newaygo County, MI

Shiso Planting Calendar

Activity When Date Range
Start Indoors March 28 Mar 28 โ€“ Apr 11
Transplant Outdoors May 30 May 30 โ€“ Jun 13
Direct Sow May 23 May 23 โ€“ Jun 13
Harvest July 25 Jul 25 โ€“ Sep 19

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

1"/week ยท Only during dry spells

๐Ÿ“… Days to Maturity

50โ€“70 days

๐Ÿงช Soil pH

Needs 5.5โ€“7 ยท Your soil: ideal

๐Ÿ—บ๏ธ USDA Zone

Zone 5b

๐Ÿ“† Growing Season

142 days in Newaygo County

Growing Tips for Shiso in Newaygo County

Direct sow Shiso outdoors after May 16 in Newaygo County when soil has warmed and frost danger has passed.

General growing tips

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

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Shiso in Newaygo County, MI?

Newaygo County is in Zone 5b with an average last frost of May 16. Plan your Shiso planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Newaygo County, MI?

Newaygo County, Michigan is in USDA Hardiness Zone 5b. The average last spring frost is May 16 and first fall frost is October 5.

๐ŸŒฑ

Plan Your Garden with Confidence

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

Get Your Free Garden Planner →

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