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When to plant Shiso in Stearns County, MN

For Stearns County, gardeners: plant Shiso May 10 through May 31 once soil reads 50°F.

When to Plant Shiso in Stearns County, MN

Stearns County, Minnesota Zone 4b June

Your June game plan for Stearns County, Minnesota

Your garden in Stearns County, Minnesota is working on a schedule, even when you're not. Here's where you should be this June.

Avg. last frost May 3
Avg. first frost October 6
Soil temp (4") 65°F
Watering Low
Pest pressure High
Daylight 15.5 hrs
  1. Time to start shiso inside

    Give them 6–8 weeks indoors before the last frost and you'll transplant into warm soil with seedlings that are already leaping.

July will be here before you know it — start on
  • First harvests: shiso

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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.

Stearns County, Minnesota is in USDA Zone 4b. The average last spring frost is May 3 and the first fall frost is October 6, giving you a growing season of approximately 156 days.

At an elevation of 772 feet, Stearns County receives approximately 37.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 82°F, so choose short-season varieties of Shiso to ensure they mature before fall.

Stearns County, MN (Zone 4b) Moderate season
156 days
Last Spring Frost May 3
156 growing days
First Fall Frost October 6

Stearns County Soil Profile

Soil Type

Silt Loam

Soil pH

5.8-6.7

Drainage

Well Drained

Shiso Planting Risk Windows

Early Start (70% safe) ✓ Fits season (24 days to spare)
Start indoors: Mar 1 Transplant: May 17 🍅 Harvest: Jul 12 – Sep 6
Recommended (50%) ✓ Fits season (23 days to spare)
Start indoors: Mar 8 Transplant: May 24 🍅 Harvest: Jul 19 – Sep 13
Safe Start (90%) ✓ Fits season (19 days to spare)
Start indoors: Mar 24 Transplant: Jun 9 🍅 Harvest: Aug 4 – Sep 29

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 Stearns County

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

Soil pH

Your soil pH (5.8–6.7) is within Shiso's preferred range (5.5–7.0).

Soil Texture

The silt loam soil in Stearns County is excellent for Shiso — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (3.9%). Annual compost additions will help Shiso.

How to Plant Shiso

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

Succession Planting Shiso

3
successive plantings in your 156-day season

Sow every 5.7 weeks. Last sowing by Jul 28 to harvest before frost.

Shiso Water Budget

Plant needs
1.0″/week
Rainfall provides
1.0″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

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 1.5" 0" ❄️ Dormant
Feb 1.8" 0" ❄️ Dormant
Mar 2.5" 0" ❄️ Dormant
Apr 3.5" 0" ❄️ Dormant
May 4.3" 4.2" 0.1" 💧 Light watering
Jun 4.3" 5" 0" ✅ Rainfall sufficient
Jul 4.3" 3.9" 0.4" 💧 Light watering
Aug 4.3" 3.6" 0.7" 💧 Light watering
Sep 4.3" 3.9" 0.4" 💧 Light watering
Oct 4.3" 2.8" 1.5" 💧 Light watering
Nov 2.7" 0" ❄️ Dormant
Dec 2.5" 0" ❄️ Dormant

Water needs are for active growing months only (May–Oct in Stearns County). Supplement amounts are based on average rainfall — 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" — every day above 50°F 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 ~690 GDD — county provides 1,794 GDD Excellent fit

Shiso Planting Timeline — Stearns County, MN

Shiso Planting Calendar

Activity When Date Range
Start Indoors March 8 Mar 8 – Mar 22
Transplant Outdoors May 24 May 24 – Jun 7
Direct Sow May 10 May 10 – May 31
Harvest July 19 Jul 19 – Sep 13

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · Natural rainfall sufficient

📅 Days to Maturity

50–70 days

🧪 Soil pH

Needs 5.5–7 · Your soil: ideal

🗺️ USDA Zone

Zone 4b

📆 Growing Season

156 days in Stearns County

Growing Tips for Shiso in Stearns County

Direct sow Shiso outdoors after May 03 in Stearns 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 Stearns County, MN?

Stearns County is in Zone 4b with an average last frost of May 3. Plan your Shiso planting based on this frost date — see the calendar above for exact timing.

What planting zone is Stearns County, MN?

Stearns County, Minnesota is in USDA Hardiness Zone 4b. The average last spring frost is May 3 and first fall frost is October 6.

When should I plant Shiso in Stearns County, MN?

In Stearns County, MN, plant Shiso after the last frost (around May 3) and before the first frost (around October 6). Best results when soil holds above 50°F.

What growing zone is Stearns County, MN for Shiso?

Stearns County sits in USDA Zone 4b. Shiso grows reliably in zones 3a through 11b, so it's a good fit here.

Can Shiso grow in Stearns County's climate?

Yes — Shiso grows well in Stearns County's temperate climate. Stearns County averages a 156-day frost-free season, with last frost around May 3 and first frost around October 6.

🌱

Your Stearns County Garden Planner — Free

A 22-page printable planner built for Stearns County (Zone 4b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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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 Stearns County, MN. Local conditions may vary. Last updated: June 2026.

Sources & credits

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