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When to plant Shiso in Johnson County, KY

The best window to plant Shiso in Johnson County, is April 21–May 12, when soil warms to 50°F. Last frost typically hits April 14; first frost October 26.

When to Plant Shiso in Johnson County, KY

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.

Johnson County, Kentucky is in USDA Zone 7a. The average last spring frost is April 14 and the first fall frost is October 26, giving you a growing season of approximately 195 days.

At an elevation of 3,308 feet, Johnson County receives approximately 47 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Shiso during the growing season.

Johnson County, KY (Zone 7a) Moderate season
195 days
Last Spring Frost April 14
195 growing days
First Fall Frost October 26

Johnson County Soil Profile

Soil Type

Silt Loam

Soil pH

5.3-7

Drainage

Well Drained

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 3.4" 0" ❄️ Dormant
Feb 4.2" 0" ❄️ Dormant
Mar 5.1" 0" ❄️ Dormant
Apr 4.3" 4.1" 0.2" 💧 Light watering
May 4.3" 3.5" 0.8" 💧 Light watering
Jun 4.3" 4.6" 0" ✅ Rainfall sufficient
Jul 4.3" 4.6" 0" ✅ Rainfall sufficient
Aug 4.3" 4.4" 0" ✅ Rainfall sufficient
Sep 4.3" 3.5" 0.8" 💧 Light watering
Oct 4.3" 2.6" 1.7" 💧 Light watering
Nov 3.6" 0" ❄️ Dormant
Dec 3.5" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Johnson County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Shiso Planting Timeline — Johnson County, KY

Shiso Planting Calendar

Activity When Date Range
Start Indoors February 24 Feb 24 – Mar 10
Transplant Outdoors April 28 Apr 28 – May 12
Direct Sow April 21 Apr 21 – May 12
Harvest June 23 Jun 23 – Aug 18

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

50–70 days

🧪 Soil pH

Needs 5.5–7 · Your soil: N/A

🗺️ USDA Zone

Zone 7a

📆 Growing Season

195 days in Johnson County

Growing Tips for Johnson 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

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Shiso in Johnson County, KY?

Johnson County is in Zone 7a with an average last frost of April 14. Plan your Shiso planting based on this frost date — see the calendar above for exact timing.

What planting zone is Johnson County, KY?

Johnson County, Kentucky is in USDA Hardiness Zone 7a. The average last spring frost is April 14 and first fall frost is October 26.

When should I plant Shiso in Johnson County, KY?

In Johnson County, KY, plant Shiso after the last frost (around April 14) and before the first frost (around October 26). Best results when soil holds above 50°F.

What growing zone is Johnson County, KY for Shiso?

Johnson County sits in USDA Zone 7a. Shiso grows reliably in zones 3a through 11b, so it's a good fit here.

Can Shiso grow in Johnson County's climate?

Yes — Shiso grows well in Johnson County's temperate climate. Johnson County averages a 195-day frost-free season, with last frost around April 14 and first frost around October 26.

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Your Johnson County Garden Planner — Free

A 22-page printable planner built for Johnson County (Zone 7a). 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 Johnson County, KY. Local conditions may vary. Last updated: July 2026.

Sources & credits

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