When to Plant Shiso in Hamilton County, FL
What to do in May
May is a pivotal month for Hamilton County, Florida gardens. Focus on these tasks first and you'll set up the rest of the season for success.
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Harvest shiso as they ripen
Morning harvests are best — cooler temperatures mean crisper produce and longer fridge life.
June prep starts now
- 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.
Hamilton County, Florida is in USDA Zone 9a. The average last spring frost is March 4 and the first fall frost is November 26, giving you a growing season of approximately 267 days.
At an elevation of 279 feet, Hamilton County receives approximately 61.2 inches of rainfall annually with predominantly sand soil. Summer highs average 93°F, providing good warmth for Shiso during the growing season. Sandy soil warms quickly in spring — great for early planting — but Shiso will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Shiso root diseases.
Hamilton County Soil Profile
Soil Type
Sand
Soil pH
5.2-5.7
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 Hamilton County
How your county's soil matches Shiso's growing requirements.
Soil pH
Your soil pH (5.2–5.7) is more acidic than Shiso prefers (5.5–7.0). Add garden lime to raise pH.
Soil Texture
Sandy soil in Hamilton 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 (1.4%). Add 2-3 inches of compost before planting Shiso.
How to Plant Shiso
Succession Planting Shiso
Sow every 5.7 weeks. Last sowing by Sep 17 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 | — | 3.2" | 0" | ❄️ Dormant |
| Feb | — | 3.1" | 0" | ❄️ Dormant |
| Mar | 4.3" | 3.3" | 1" | 💧 Light watering |
| Apr | 4.3" | 2.4" | 1.9" | 💧 Light watering |
| May | 4.3" | 3.4" | 0.9" | 💧 Light watering |
| Jun | 4.3" | 9.3" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 8.8" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 9.2" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 8.5" | 0" | ✅ Rainfall sufficient |
| Oct | 4.3" | 5" | 0" | ✅ Rainfall sufficient |
| Nov | 4.3" | 2.7" | 1.6" | 💧 Light watering |
| Dec | — | 2.4" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Hamilton 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 — Hamilton County, FL
Shiso Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 21 | Jan 21 – Feb 4 |
| Transplant Outdoors | March 11 | Mar 11 – Mar 25 |
| Direct Sow | March 11 | Mar 11 – Apr 1 |
| Harvest | May 6 | May 6 – Jul 1 |
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 · 1-2 times/week
📅 Days to Maturity
50–70 days
🧪 Soil pH
Needs 5.5–7 · Your soil: too_acidic
🗺️ USDA Zone
Zone 9a
📆 Growing Season
267 days in Hamilton County
Growing Tips for Shiso in Hamilton County
Direct sow Shiso outdoors after March 04 in Hamilton County when soil has warmed and frost danger has passed.
Sandy soil in Hamilton County dries quickly — 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 →
Shiso in Other Locations
Frequently Asked Questions
When should I plant Shiso in Hamilton County, FL?
Hamilton County is in Zone 9a with an average last frost of March 4. Plan your Shiso planting based on this frost date — see the calendar above for exact timing.
What planting zone is Hamilton County, FL?
Hamilton County, Florida is in USDA Hardiness Zone 9a. The average last spring frost is March 4 and first fall frost is November 26.
Your Hamilton County Garden Planner — Free
A 24-page printable planner built for Hamilton 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.