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When to Plant Shiso in Jackson County, FL

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.

Jackson County, Florida is in USDA Zone 8b. The average last spring frost is March 6 and the first fall frost is November 19, giving you a growing season of approximately 258 days.

At an elevation of 223 feet, Jackson County receives approximately 48.5 inches of rainfall annually with predominantly sand soil. Summer highs average 92ยฐF, providing good warmth for Shiso during the growing season. Sandy soil warms quickly in spring โ€” great for early planting โ€” but Shiso will need more frequent watering and organic matter to retain nutrients.

Jackson County, FL (Zone 8b) Long season
258 days
Last Spring Frost March 6
258 growing days
First Fall Frost November 19

Jackson County Soil Profile

Soil Type

Sand

Soil pH

5.1-6

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (131 days to spare)
Start indoors: Jan 10 Transplant: Mar 14 🍅 Harvest: May 9 – Jul 4
Recommended (50%) ✓ Fits season (132 days to spare)
Start indoors: Jan 16 Transplant: Mar 20 🍅 Harvest: May 15 – Jul 10
Safe Start (90%) ✓ Fits season (137 days to spare)
Start indoors: Feb 6 Transplant: Apr 10 🍅 Harvest: Jun 5 – Jul 31

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 Jackson County

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

Soil pH

Your soil pH (5.1โ€“6.0) overlaps with Shiso's range (5.5โ€“7.0), though not a perfect match.

Soil Texture

Sandy soil in Jackson County warms quickly in spring but drains fast. Shiso will need more frequent watering and regular compost additions to retain nutrients.

Drainage

Drainage is adequate for Shiso.

Organic Matter

Organic matter is low (1.3%). Add 2-3 inches of compost before planting Shiso.

How to Plant Shiso

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

Succession Planting Shiso

6
successive plantings in your 258-day season

Sow every 5.7 weeks. Last sowing by Sep 10 to harvest before frost.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.8″/week
You supply
0.6″/week
Watering frequency 1-2 times/week
Season total 1,407 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€” 2.3" 0" โ„๏ธ Dormant
Feb โ€” 2.6" 0" โ„๏ธ Dormant
Mar 4.3" 2.7" 1.6" ๐Ÿ’ง Light watering
Apr 4.3" 1.9" 2.4" ๐Ÿšฟ Regular watering
May 4.3" 3.2" 1.1" ๐Ÿ’ง Light watering
Jun 4.3" 7" 0" โœ… Rainfall sufficient
Jul 4.3" 7.2" 0" โœ… Rainfall sufficient
Aug 4.3" 7.5" 0" โœ… Rainfall sufficient
Sep 4.3" 6.1" 0" โœ… Rainfall sufficient
Oct 4.3" 4" 0.3" ๐Ÿ’ง Light watering
Nov 4.3" 1.9" 2.4" ๐Ÿšฟ Regular watering
Dec โ€” 2.1" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Marโ€“Nov in Jackson 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 ~1,140 GDD — county provides 4,902 GDD Excellent fit

Shiso Planting Timeline โ€” Jackson County, FL

Shiso Planting Calendar

Activity When Date Range
Start Indoors January 16 Jan 16 โ€“ Jan 30
Transplant Outdoors March 20 Mar 20 โ€“ Apr 3
Direct Sow March 13 Mar 13 โ€“ Apr 3
Harvest May 15 May 15 โ€“ Jul 10

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

1"/week ยท 1-2 times/week

๐Ÿ“… Days to Maturity

50โ€“70 days

๐Ÿงช Soil pH

Needs 5.5โ€“7 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 8b

๐Ÿ“† Growing Season

258 days in Jackson County

Growing Tips for Shiso in Jackson County

Direct sow Shiso outdoors after March 06 in Jackson County when soil has warmed and frost danger has passed.

Sandy soil in Jackson County dries quickly โ€” mulch Shiso with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

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 Jackson County, FL?

Jackson County is in Zone 8b with an average last frost of March 6. Plan your Shiso planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Jackson County, FL?

Jackson County, Florida is in USDA Hardiness Zone 8b. The average last spring frost is March 6 and first fall frost is November 19.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Jackson County gardeners in Zone 8b organize planting dates, track what's growing, and never miss a planting window.

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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 Jackson County, FL. Local conditions may vary. Last updated: April 2026.