When to Plant Shiso in USDA Zone 4a
Zone 4a gardeners: here's your June plan
Here's what deserves your attention in Zone 4a this month. Everything below is tailored to Zone 4a and timed around your local frost dates.
-
Plant out shiso
Frost risk is low now in Zone 4a. If you've been covering beds overnight, you can stop.
To set up a strong July, finish these tasks
- Starting indoors: shiso
- 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.
In Zone 4a, the average last spring frost is around May 6 and the first fall frost is around September 28, giving you a growing season of approximately 145 days.
Shiso Planting Timeline — Zone 4a
Where Is USDA Zone 4a?
The map below highlights the states that contain Zone 4a. Click any state to see the Shiso planting schedule for that location.
Shiso Planting Calendar — Zone 4a
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 11 | Mar 11 – Mar 25 |
| Transplant Outdoors | May 27 | May 27 – Jun 10 |
| Direct Sow | May 13 | May 13 – Jun 3 |
| Harvest | July 22 | Jul 22 – Sep 16 |
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 | Transplant Outdoors Direct Sow |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Free Zone 4a Planting Calendar PDF
Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 4a with start dates, transplant windows, and harvest times.
Growing Conditions
Sun
Partial Shade (3-6 hours)
💧 Water
Moderate — regular watering
Days to Maturity
50–70 days
Soil pH
5.5 – 7
Zone Temperature Range
-30°F to -25°F average annual minimum
Growing Season
145 days (Zone 4a average)
Planting Specifications
| Planting Depth | 0.5 inches |
| Plant Spacing | 8 inches apart |
| Row Spacing | 12 inches between rows |
Succession Planting Shiso in Zone 4a
Sow every 5.7 weeks for continuous harvest throughout the season.
Growing Tips for Shiso in Zone 4a
Zone 4a has a short growing season (~145 days). Start Shiso indoors early and use season-extension techniques like row covers and cold frames.
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
The Gardener's Encyclopedia to Companion Planting
The pairings that make vegetables, herbs, and flowers grow better — and the ones that quietly wreck a bed.
- Proven pairings for 200+ vegetables, herbs, flowers, and fruits
- Full seed-starting + planting schedule with timing and spacing
- Bonus: square-foot gardening guide + printable seasonal planners
Saving Shiso Seeds
Recommended for Your Garden
Full-spectrum LED lights for starting seeds indoors when daylight is limited.
Warm soil for faster germination of heat-loving crops like tomatoes and peppers.
Protect plants from frost, wind, and pests while letting light and water through.
Related Plants
Shiso in Other Zones
Shiso by State
- Alabama
- Alaska
- Arizona
- Arkansas
- California
- Colorado
- Connecticut
- Delaware
- Florida
- Georgia
- Hawaii
- Idaho
- Illinois
- Indiana
- Iowa
- Kansas
- Kentucky
- Louisiana
- Maine
- Maryland
- Massachusetts
- Michigan
- Minnesota
- Mississippi
- Missouri
- Montana
- Nebraska
- Nevada
- New Hampshire
- New Jersey
- New Mexico
- New York
- North Carolina
- North Dakota
- Ohio
- Oklahoma
- Oregon
- Pennsylvania
- Rhode Island
- South Carolina
- South Dakota
- Tennessee
- Texas
- Utah
- Vermont
- Virginia
- Washington
- West Virginia
- Wisconsin
- Wyoming
Frequently Asked Questions
When should I plant Shiso in Zone 4a?
In Zone 4a, plan your Shiso planting around the average last frost date of May 6. Start seeds indoors around March 11. Direct sow outdoors around May 13. Transplant seedlings around May 27.
Can Shiso grow in Zone 4a?
Yes, Shiso can grow well in Zone 4a, hardy in USDA zones 3a through 11b. Zone 4a has a growing season of approximately 145 days, which is sufficient for Shiso (50-70 days to maturity).
When can I harvest Shiso in Zone 4a?
In Zone 4a, expect to harvest Shiso from July 22 – September 16. Shiso takes 50-70 days from planting to harvest.
What is the last frost date for Zone 4a?
The average last spring frost in Zone 4a is around May 6, and the first fall frost is around September 28. This gives a growing season of approximately 145 days. These are 50% probability dates — actual frost dates vary year to year.
What should I plant next to Shiso?
Good companion plants for Shiso include Tomatoes, Peppers. These companions can help with pest control, pollination, and nutrient sharing.
Your Zone 4a Garden Planner — Free
A 22-page printable planner tailored to Zone 4a. Planting dates, monthly task lists, harvest log, seed inventory, and succession charts — everything you need to plan a full season.