When to Plant Shiso in Coffee County, GA
Your May gardening checklist
Welcome to May in Zone 9a. These are the moves that will have the biggest impact on your growing season.
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Start harvesting shiso
Morning harvests are best — cooler temperatures mean crisper produce and longer fridge life.
Coming up in June — start thinking about
- First harvests: shiso
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.
Coffee County, Georgia is in USDA Zone 9a. The average last spring frost is March 8 and the first fall frost is November 22, giving you a growing season of approximately 259 days.
At an elevation of 110 feet, Coffee County receives approximately 59.5 inches of rainfall annually with predominantly clay loam soil. Summer highs average 95°F, so Shiso may need afternoon shade and extra watering during peak heat. Clay soil retains moisture well for Shiso, but amend with compost to improve drainage and prevent root rot. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Shiso root diseases.
Coffee County Soil Profile
Soil Type
Clay Loam
Soil pH
5.6-6.3
Drainage
Well Drained
Plant Planting Risk Windows
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 Coffee County
How your county's soil matches Shiso's growing requirements.
Soil pH
Your soil pH (5.6–6.3) is within Shiso's preferred range (5.5–7.0).
Soil Texture
The clay loam soil in Coffee County is excellent for Shiso — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Shiso.
Organic Matter
Organic matter is moderate (2.5%). Annual compost additions will help Shiso.
How to Plant Shiso
Succession Planting Shiso
Sow every 5.7 weeks. Last sowing by Sep 13 to harvest before frost.
Plant Water Budget
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 | — | 5.1" | 0" | ❄️ Dormant |
| Feb | — | 4.8" | 0" | ❄️ Dormant |
| Mar | 4.3" | 5.9" | 0" | ✅ Rainfall sufficient |
| Apr | 4.3" | 4.8" | 0" | ✅ Rainfall sufficient |
| May | 4.3" | 4.9" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 4.8" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 5.9" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 5.8" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 4.4" | 0" | ✅ Rainfall sufficient |
| Oct | 4.3" | 3.6" | 0.7" | 💧 Light watering |
| Nov | 4.3" | 4.6" | 0" | ✅ Rainfall sufficient |
| Dec | — | 4.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Coffee 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 Planting Timeline — Coffee County, GA
Shiso Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 25 | Jan 25 – Feb 8 |
| Transplant Outdoors | March 15 | Mar 15 – Mar 29 |
| Direct Sow | March 15 | Mar 15 – Apr 5 |
| Harvest | May 10 | May 10 – Jul 5 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| February | Start Indoors |
| March | Transplant Outdoors Direct Sow |
| April | Direct Sow |
| May | Harvest |
| June | Harvest |
| July | Harvest |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
1"/week · Natural rainfall sufficient
📅 Days to Maturity
50–70 days
🧪 Soil pH
Needs 5.5–7 · Your soil: ideal
🗺️ USDA Zone
Zone 9a
📆 Growing Season
259 days in Coffee County
Growing Tips for Shiso in Coffee County
Direct sow Shiso outdoors after March 08 in Coffee County when soil has warmed and frost danger has passed.
With Coffee County's clay soil (32% clay), work in 3-4 inches of compost before planting Shiso. Avoid tilling when soil is wet to prevent compaction.
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 →
Shiso in Other Locations
Frequently Asked Questions
When should I plant Shiso in Coffee County, GA?
Coffee County is in Zone 9a with an average last frost of March 8. Plan your Shiso planting based on this frost date — see the calendar above for exact timing.
What planting zone is Coffee County, GA?
Coffee County, Georgia is in USDA Hardiness Zone 9a. The average last spring frost is March 8 and first fall frost is November 22.
Your Coffee County Garden Planner — Free
A 24-page printable planner built for Coffee County (Zone 9a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.