When to Plant Shiso in Caldwell County, TX
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.
Caldwell County, Texas is in USDA Zone 9a. The average last spring frost is February 27 and the first fall frost is December 1, giving you a growing season of approximately 277 days.
At an elevation of 3,482 feet, Caldwell County receives approximately 60.8 inches of rainfall annually with predominantly clay soil. Summer highs average 90°F, providing good warmth for Shiso during the growing season. 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.
Caldwell County Soil Profile
Soil Type
Clay
Soil pH
6.8-8.1
Drainage
Well Drained
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 | — | 1.4" | 0" | ❄️ Dormant |
| Feb | 4.3" | 2.1" | 2.2" | 🚿 Regular watering |
| Mar | 4.3" | 4.1" | 0.2" | 💧 Light watering |
| Apr | 4.3" | 6" | 0" | ✅ Rainfall sufficient |
| May | 4.3" | 9.9" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 9.2" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 7.5" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 7.9" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 5.6" | 0" | ✅ Rainfall sufficient |
| Oct | 4.3" | 3.8" | 0.5" | 💧 Light watering |
| Nov | 4.3" | 1.8" | 2.5" | 🚿 Regular watering |
| Dec | 4.3" | 1.5" | 2.8" | 🚿 Regular watering |
Water needs are for active growing months only (Feb–Dec in Caldwell County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Shiso Planting Timeline — Caldwell County, TX
Shiso Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 16 | Jan 16 – Jan 30 |
| Transplant Outdoors | March 6 | Mar 6 – Mar 20 |
| Direct Sow | March 6 | Mar 6 – Mar 27 |
| Harvest | May 1 | May 1 – Jun 26 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| February | — |
| March | Transplant Outdoors Direct Sow |
| April | — |
| May | Harvest |
| June | Harvest |
| July | — |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
Moderate — regular watering
📅 Days to Maturity
50–70 days
🧪 Soil pH
Needs 5.5–7 · Your soil: N/A
🗺️ USDA Zone
Zone 9a
📆 Growing Season
277 days in Caldwell County
Growing Tips for Caldwell County
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 Caldwell County, TX?
Caldwell County is in Zone 9a with an average last frost of February 27. Plan your Shiso planting based on this frost date — see the calendar above for exact timing.
What planting zone is Caldwell County, TX?
Caldwell County, Texas is in USDA Hardiness Zone 9a. The average last spring frost is February 27 and first fall frost is December 1.
Your Caldwell County Garden Planner — Free
A 22-page printable planner built for Caldwell 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.