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When to plant Shiso in Knott County, KY

The best window to plant Shiso in Knott County, is April 30–May 21, when soil warms to 50°F. Last frost typically hits April 23; first frost October 18.

When to Plant Shiso in Knott County, KY

Knott County, Kentucky Zone 7a July

July to-do list for Knott County, Kentucky

We've pulled the most time-sensitive tasks for Knott County, Kentucky this July and put them front and centre. Tackle them in order.

Avg. last frost April 23
Avg. first frost October 18
Soil temp (4") 78°F
Watering Low
Pest pressure High
Daylight 14.3 hrs
  1. It's harvest week for shiso

    Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.

Before August arrives, get these ready
  • 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.

Knott County, Kentucky is in USDA Zone 7a. The average last spring frost is April 23 and the first fall frost is October 18, giving you a growing season of approximately 178 days.

At an elevation of 2,201 feet, Knott County receives approximately 40.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Shiso during the growing season.

Knott County, KY (Zone 7a) Moderate season
178 days
Last Spring Frost April 23
178 growing days
First Fall Frost October 18

Knott County Soil Profile

Soil Type

Silt Loam

Soil pH

5.4-6.8

Drainage

Well Drained

Shiso Planting Risk Windows

Early Start (70% safe) ✓ Fits season (58 days to spare)
Start indoors: Feb 25 Transplant: Apr 29 🍅 Harvest: Jun 24 – Aug 19
Recommended (50%) ✓ Fits season (52 days to spare)
Start indoors: Mar 5 Transplant: May 7 🍅 Harvest: Jul 2 – Aug 27
Safe Start (90%) ✓ Fits season (46 days to spare)
Start indoors: Mar 24 Transplant: May 26 🍅 Harvest: Jul 21 – Sep 15

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 Knott County

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

Soil pH

Your soil pH (5.4–6.8) overlaps with Shiso's range (5.5–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.5%). Annual compost additions will help Shiso.

How to Plant Shiso

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

Succession Planting Shiso

4
successive plantings in your 178-day season

Sow every 5.7 weeks. Last sowing by Aug 09 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 59 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 3.2" 0" ❄️ Dormant
Feb 3.3" 0" ❄️ Dormant
Mar 4.2" 0" ❄️ Dormant
Apr 4.3" 3.2" 1.1" 💧 Light watering
May 4.3" 3.7" 0.6" 💧 Light watering
Jun 4.3" 3.1" 1.2" 💧 Light watering
Jul 4.3" 4.6" 0" ✅ Rainfall sufficient
Aug 4.3" 3.5" 0.8" 💧 Light watering
Sep 4.3" 3.1" 1.2" 💧 Light watering
Oct 4.3" 2.8" 1.5" 💧 Light watering
Nov 3.2" 0" ❄️ Dormant
Dec 3" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Knott 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 ~870 GDD — county provides 2,581 GDD Excellent fit

Shiso Planting Timeline — Knott County, KY

Shiso Planting Calendar

Activity When Date Range
Start Indoors March 5 Mar 5 – Mar 19
Transplant Outdoors May 7 May 7 – May 21
Direct Sow April 30 Apr 30 – May 21
Harvest July 2 Jul 2 – Aug 27

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

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April Direct Sow
May Transplant Outdoors Direct Sow
June
July Harvest
August Harvest
September
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: acceptable

🗺️ USDA Zone

Zone 7a

📆 Growing Season

178 days in Knott County

Growing Tips for Shiso in Knott County

Direct sow Shiso outdoors after April 23 in Knott 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 Knott County, KY?

Knott County is in Zone 7a with an average last frost of April 23. Plan your Shiso planting based on this frost date — see the calendar above for exact timing.

What planting zone is Knott County, KY?

Knott County, Kentucky is in USDA Hardiness Zone 7a. The average last spring frost is April 23 and first fall frost is October 18.

When should I plant Shiso in Knott County, KY?

In Knott County, KY, plant Shiso after the last frost (around April 23) and before the first frost (around October 18). Best results when soil holds above 50°F.

What growing zone is Knott County, KY for Shiso?

Knott 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 Knott County's climate?

Yes — Shiso grows well in Knott County's temperate climate. Knott County averages a 178-day frost-free season, with last frost around April 23 and first frost around October 18.

🌱

Your Knott County Garden Planner — Free

A 22-page printable planner built for Knott 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 Knott County, KY. 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.