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When to plant Shiso in Steele County, MN

Steele County's spring Shiso window runs May 5 through May 26. be cautious and check the 10-day forecast before planting tender crops.

When to Plant Shiso in Steele County, MN

Steele County, Minnesota Zone 4b July

July in the garden — Steele County, Minnesota

Your Steele County, Minnesota garden is entering a new phase. Here's what's on the schedule for July and why each task matters now.

Avg. last frost April 28
Avg. first frost October 7
Soil temp (4") 72°F
Watering Low
Pest pressure High
Daylight 15 hrs
  1. Harvest shiso as they ripen

    Don't tug. Use scissors or pruners for clean cuts — torn stems invite disease.

A few tasks this July that'll pay off in August
  • 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.

Steele County, Minnesota is in USDA Zone 4b. The average last spring frost is April 28 and the first fall frost is October 7, giving you a growing season of approximately 162 days.

At an elevation of 1,184 feet, Steele County receives approximately 37.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Shiso to ensure they mature before fall.

Steele County, MN (Zone 4b) Moderate season
162 days
Last Spring Frost April 28
162 growing days
First Fall Frost October 7

Steele County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-6.7

Drainage

Well Drained

Shiso Planting Risk Windows

Early Start (70% safe) ✓ Fits season (26 days to spare)
Start indoors: Feb 27 Transplant: May 15 🍅 Harvest: Jul 10 – Sep 4
Recommended (50%) ✓ Fits season (29 days to spare)
Start indoors: Mar 3 Transplant: May 19 🍅 Harvest: Jul 14 – Sep 8
Safe Start (90%) ✓ Fits season (22 days to spare)
Start indoors: Mar 19 Transplant: Jun 4 🍅 Harvest: Jul 30 – Sep 24

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 Steele County

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

Soil pH

Your soil pH (5.9–6.7) is within Shiso's preferred range (5.5–7.0).

Soil Texture

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

Organic Matter

Organic matter is excellent (4.8%) — 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 162-day season

Sow every 5.7 weeks. Last sowing by Jul 29 to harvest before frost.

Shiso Water Budget

Plant needs
1.0″/week
Rainfall provides
1.0″/week
You supply
0.0″/week
Watering frequency Only during dry spells
Season total 35 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 2.3" 0" ❄️ Dormant
Apr 4.3" 3.7" 0.6" 💧 Light watering
May 4.3" 4.4" 0" ✅ Rainfall sufficient
Jun 4.3" 4.8" 0" ✅ Rainfall sufficient
Jul 4.3" 4.1" 0.2" 💧 Light watering
Aug 4.3" 3.6" 0.7" 💧 Light watering
Sep 4.3" 3.6" 0.7" 💧 Light watering
Oct 4.3" 3.4" 0.9" 💧 Light watering
Nov 2.3" 0" ❄️ Dormant
Dec 2.4" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Steele 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 ~780 GDD — county provides 2,106 GDD Excellent fit

Shiso Planting Timeline — Steele County, MN

Shiso Planting Calendar

Activity When Date Range
Start Indoors March 3 Mar 3 – Mar 17
Transplant Outdoors May 19 May 19 – Jun 2
Direct Sow May 5 May 5 – May 26
Harvest July 14 Jul 14 – Sep 8

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 · Only during dry spells

📅 Days to Maturity

50–70 days

🧪 Soil pH

Needs 5.5–7 · Your soil: ideal

🗺️ USDA Zone

Zone 4b

📆 Growing Season

162 days in Steele County

Growing Tips for Shiso in Steele County

Direct sow Shiso outdoors after April 28 in Steele 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 Steele County, MN?

Steele County is in Zone 4b with an average last frost of April 28. Plan your Shiso planting based on this frost date — see the calendar above for exact timing.

What planting zone is Steele County, MN?

Steele County, Minnesota is in USDA Hardiness Zone 4b. The average last spring frost is April 28 and first fall frost is October 7.

When should I plant Shiso in Steele County, MN?

In Steele County, MN, plant Shiso after the last frost (around April 28) and before the first frost (around October 7). Best results when soil holds above 50°F.

What growing zone is Steele County, MN for Shiso?

Steele 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 Steele County's climate?

Yes — Shiso grows well in Steele County's temperate climate. Steele County averages a 162-day frost-free season, with last frost around April 28 and first frost around October 7.

🌱

Your Steele County Garden Planner — Free

A 22-page printable planner built for Steele 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 Steele County, MN. 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.