When to Plant Shiso in Walsh County, ND
Your May game plan for Walsh County, North Dakota
Here's what deserves your attention in Walsh County, North Dakota this month. Everything below is tailored to Zone 4a and timed around your local frost dates.
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Plant shiso from seed, right in the garden
Sow every 2 weeks for a continuous harvest. A single big planting means a single big glut.
Get ahead of June
- Transplants going out: 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.
Walsh County, North Dakota is in USDA Zone 4a. The average last spring frost is May 14 and the first fall frost is September 30, giving you a growing season of approximately 139 days.
At an elevation of 553 feet, Walsh County receives approximately 32.7 inches of rainfall annually with predominantly loam soil. Summer highs average 81°F, so choose short-season varieties of Shiso to ensure they mature before fall.
Walsh County Soil Profile
Soil Type
Loam
Soil pH
6.2-7.5
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 Walsh County
How your county's soil matches Shiso's growing requirements.
Soil pH
Your soil pH (6.2–7.5) overlaps with Shiso's range (5.5–7.0), though not a perfect match.
Soil Texture
The loam soil in Walsh County is excellent for Shiso — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (3.6%). Annual compost additions will help Shiso.
How to Plant Shiso
Succession Planting Shiso
Sow every 5.7 weeks. Last sowing by Jul 22 to harvest before frost.
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
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 | — | 0.7" | 0" | ❄️ Dormant |
| Feb | — | 1.2" | 0" | ❄️ Dormant |
| Mar | — | 2.2" | 0" | ❄️ Dormant |
| Apr | — | 3.1" | 0" | ❄️ Dormant |
| May | 4.3" | 5.2" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 5.3" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 3.6" | 0.7" | 💧 Light watering |
| Aug | 4.3" | 4.2" | 0.1" | 💧 Light watering |
| Sep | 4.3" | 3.2" | 1.1" | 💧 Light watering |
| Oct | — | 1.9" | 0" | ❄️ Dormant |
| Nov | — | 1.1" | 0" | ❄️ Dormant |
| Dec | — | 0.9" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Walsh 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 — Walsh County, ND
Shiso Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 19 | Mar 19 – Apr 2 |
| Transplant Outdoors | June 4 | Jun 4 – Jun 18 |
| Direct Sow | May 21 | May 21 – Jun 11 |
| Harvest | July 30 | Jul 30 – Sep 24 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors |
| May | Direct Sow |
| June | Transplant Outdoors Direct Sow |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
1"/week · Only during dry spells
📅 Days to Maturity
50–70 days
🧪 Soil pH
Needs 5.5–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 4a
📆 Growing Season
139 days in Walsh County
Growing Tips for Shiso in Walsh County
Direct sow Shiso outdoors after May 14 in Walsh 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 Walsh County, ND?
Walsh County is in Zone 4a with an average last frost of May 14. Plan your Shiso planting based on this frost date — see the calendar above for exact timing.
What planting zone is Walsh County, ND?
Walsh County, North Dakota is in USDA Hardiness Zone 4a. The average last spring frost is May 14 and first fall frost is September 30.
Your Walsh County Garden Planner — Free
A 24-page printable planner built for Walsh County (Zone 4a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.