When to Plant Shiso in Mifflin County, PA
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.
Mifflin County, Pennsylvania is in USDA Zone 7a. The average last spring frost is April 24 and the first fall frost is October 22, giving you a growing season of approximately 181 days.
At an elevation of 1,022 feet, Mifflin County receives approximately 45.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Shiso during the growing season.
Mifflin County Soil Profile
Soil Type
Silt Loam
Soil pH
4.9-6.4
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 | — | 3.1" | 0" | ❄️ Dormant |
| Feb | — | 3.1" | 0" | ❄️ Dormant |
| Mar | — | 3.9" | 0" | ❄️ Dormant |
| Apr | 4.3" | 3.6" | 0.7" | 💧 Light watering |
| May | 4.3" | 3.8" | 0.5" | 💧 Light watering |
| Jun | 4.3" | 4.4" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 4.9" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 4.7" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 3.3" | 1" | 💧 Light watering |
| Oct | 4.3" | 3.7" | 0.6" | 💧 Light watering |
| Nov | — | 3.5" | 0" | ❄️ Dormant |
| Dec | — | 3.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Mifflin County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Shiso Planting Timeline — Mifflin County, PA
Shiso Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 6 | Mar 6 – Mar 20 |
| Transplant Outdoors | May 8 | May 8 – May 22 |
| Direct Sow | May 1 | May 1 – May 22 |
| Harvest | July 3 | Jul 3 – Aug 28 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | — |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Harvest |
| August | Harvest |
| 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 7a
📆 Growing Season
181 days in Mifflin County
Growing Tips for Mifflin 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 Mifflin County, PA?
Mifflin County is in Zone 7a with an average last frost of April 24. Plan your Shiso planting based on this frost date — see the calendar above for exact timing.
What planting zone is Mifflin County, PA?
Mifflin County, Pennsylvania is in USDA Hardiness Zone 7a. The average last spring frost is April 24 and first fall frost is October 22.
Your Mifflin County Garden Planner — Free
A 22-page printable planner built for Mifflin County (Zone 7a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.