When to Plant Shiso in Dukes County, MA
This month in Dukes County, Massachusetts
May rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Dukes County, Massachusetts.
-
Move shiso into the garden
Your last frost (April 25) has passed. These warm-season crops can handle outdoor soil now.
-
Direct-sow shiso
Succession planting is the secret here. Put in a row now, another in 2 weeks, a third in 4.
To set up a strong June, finish these tasks
- Starting indoors: 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.
Dukes County, Massachusetts is in USDA Zone 7b. The average last spring frost is April 25 and the first fall frost is October 19, giving you a growing season of approximately 177 days.
At an elevation of 676 feet, Dukes County receives approximately 48.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88°F, providing good warmth for Shiso during the growing season.
Dukes County Soil Profile
Soil Type
Silt Loam
Soil pH
5.2-6.5
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 Dukes County
How your county's soil matches Shiso's growing requirements.
Soil pH
Your soil pH (5.2–6.5) overlaps with Shiso's range (5.5–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Dukes 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 (3.8%). Annual compost additions will help Shiso.
How to Plant Shiso
Succession Planting Shiso
Sow every 5.7 weeks. Last sowing by Aug 10 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 | — | 3.7" | 0" | ❄️ Dormant |
| Feb | — | 2.8" | 0" | ❄️ Dormant |
| Mar | — | 3.4" | 0" | ❄️ Dormant |
| Apr | 4.3" | 4.5" | 0" | ✅ Rainfall sufficient |
| May | 4.3" | 4.5" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 4.2" | 0.1" | 💧 Light watering |
| Jul | 4.3" | 4.8" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 4.8" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 4.4" | 0" | ✅ Rainfall sufficient |
| Oct | 4.3" | 4.1" | 0.2" | 💧 Light watering |
| Nov | — | 3.5" | 0" | ❄️ Dormant |
| Dec | — | 3.5" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Dukes 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 — Dukes County, MA
Shiso Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 7 | Mar 7 – Mar 21 |
| Transplant Outdoors | May 9 | May 9 – May 23 |
| Direct Sow | May 2 | May 2 – May 23 |
| Harvest | July 4 | Jul 4 – Aug 29 |
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
1"/week · Natural rainfall sufficient
📅 Days to Maturity
50–70 days
🧪 Soil pH
Needs 5.5–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 7b
📆 Growing Season
177 days in Dukes County
Growing Tips for Shiso in Dukes County
Direct sow Shiso outdoors after April 25 in Dukes County when soil has warmed and frost danger has passed.
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 Dukes County, MA?
Dukes County is in Zone 7b with an average last frost of April 25. Plan your Shiso planting based on this frost date — see the calendar above for exact timing.
What planting zone is Dukes County, MA?
Dukes County, Massachusetts is in USDA Hardiness Zone 7b. The average last spring frost is April 25 and first fall frost is October 19.
Your Dukes County Garden Planner — Free
A 24-page printable planner built for Dukes County (Zone 7b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.