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When to Plant Shiso in Culpeper County, VA

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.

Culpeper County, Virginia is in USDA Zone 7a. The average last spring frost is April 15 and the first fall frost is October 25, giving you a growing season of approximately 193 days.

At an elevation of 919 feet, Culpeper County receives approximately 50.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91ยฐF, providing good warmth for Shiso during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Shiso root diseases.

Culpeper County, VA (Zone 7a) Moderate season
193 days
Last Spring Frost April 15
193 growing days
First Fall Frost October 25

Culpeper County Soil Profile

Soil Type

Silt Loam

Soil pH

5.5-6.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (69 days to spare)
Start indoors: Feb 16 Transplant: Apr 20 🍅 Harvest: Jun 15 – Aug 10
Recommended (50%) ✓ Fits season (67 days to spare)
Start indoors: Feb 25 Transplant: Apr 29 🍅 Harvest: Jun 24 – Aug 19
Safe Start (90%) ✓ Fits season (62 days to spare)
Start indoors: Mar 22 Transplant: May 24 🍅 Harvest: Jul 19 – Sep 13

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 Culpeper County

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

Soil pH

Your soil pH (5.5โ€“6.7) is within Shiso's preferred range (5.5โ€“7.0).

Soil Texture

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

Organic Matter

Organic matter is moderate (2.9%). 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 193-day season

Sow every 5.7 weeks. Last sowing by Aug 16 to harvest before frost.

Plant Water Budget

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

Water stress score is 6/10 โ€” 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 โ€” 4.3" 0" โ„๏ธ Dormant
Feb โ€” 3.5" 0" โ„๏ธ Dormant
Mar โ€” 4.6" 0" โ„๏ธ Dormant
Apr 4.3" 4" 0.3" ๐Ÿ’ง Light watering
May 4.3" 4.1" 0.2" ๐Ÿ’ง Light watering
Jun 4.3" 4.5" 0" โœ… Rainfall sufficient
Jul 4.3" 5.5" 0" โœ… Rainfall sufficient
Aug 4.3" 4.1" 0.2" ๐Ÿ’ง Light watering
Sep 4.3" 3.9" 0.4" ๐Ÿ’ง Light watering
Oct 4.3" 3.6" 0.7" ๐Ÿ’ง Light watering
Nov โ€” 4.3" 0" โ„๏ธ Dormant
Dec โ€” 3.9" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Culpeper 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 ~1,095 GDD — county provides 3,522 GDD Excellent fit

Shiso Planting Timeline โ€” Culpeper County, VA

Shiso Planting Calendar

Activity When Date Range
Start Indoors February 25 Feb 25 โ€“ Mar 11
Transplant Outdoors April 29 Apr 29 โ€“ May 13
Direct Sow April 22 Apr 22 โ€“ May 13
Harvest June 24 Jun 24 โ€“ Aug 19

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

1"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

50โ€“70 days

๐Ÿงช Soil pH

Needs 5.5โ€“7 ยท Your soil: ideal

๐Ÿ—บ๏ธ USDA Zone

Zone 7a

๐Ÿ“† Growing Season

193 days in Culpeper County

Growing Tips for Shiso in Culpeper County

Direct sow Shiso outdoors after April 15 in Culpeper 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 Culpeper County, VA?

Culpeper County is in Zone 7a with an average last frost of April 15. Plan your Shiso planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Culpeper County, VA?

Culpeper County, Virginia is in USDA Hardiness Zone 7a. The average last spring frost is April 15 and first fall frost is October 25.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Culpeper County gardeners in Zone 7a 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 Culpeper County, VA. Local conditions may vary. Last updated: April 2026.