When to Plant Shiso in USDA Zone 9b
May to-do list for Zone 9b
A quick May briefing for Zone 9b gardeners — what's urgent, what's next, and what can wait.
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Collect shiso at their peak
This is the payoff month. Bring a basket, bring a friend, and get into the beds.
June prep starts now
- 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 9b, the average last spring frost is around January 25 and the first fall frost is around December 20, giving you a growing season of approximately 329 days.
Shiso Planting Timeline — Zone 9b
Where Is USDA Zone 9b?
The map below highlights the states that contain Zone 9b. Click any state to see the Shiso planting schedule for that location.
Shiso Planting Calendar — Zone 9b
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | December 14 | Dec 14 – Dec 28 |
| Transplant Outdoors | February 1 | Feb 1 – Feb 15 |
| Direct Sow | February 1 | Feb 1 – Feb 22 |
| Harvest | March 29 | Mar 29 – May 24 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Transplant Outdoors Direct Sow |
| March | Harvest |
| April | Harvest |
| May | Harvest |
| June | — |
| July | — |
| August | — |
| September | — |
| October | — |
| November | — |
| December | Start Indoors |
Free Zone 9b Planting Calendar PDF
Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 9b 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
°F to °F average annual minimum
Growing Season
329 days (Zone average)
Planting Specifications
| Planting Depth | 0.5 inches |
| Plant Spacing | 8 inches apart |
| Row Spacing | 12 inches between rows |
Succession Planting Shiso in Zone
Sow every 5.7 weeks for continuous harvest throughout the season.
Growing Tips for Shiso in Zone
Zone has a short growing season (~329 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
Start seeds indoors with reusable cell trays and humidity domes.
Test your soil pH, nitrogen, phosphorus, and potassium levels before planting.
Keep your garden organized with durable, weather-resistant plant labels.
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 9b?
In Zone 9b, plan your Shiso planting around the average last frost date of January 25. Start seeds indoors around December 14. Direct sow outdoors around February 1. Transplant seedlings around February 1.
Can Shiso grow in Zone 9b?
Yes, Shiso can grow well in Zone 9b, hardy in USDA zones 3a through 11b. Zone 9b has a growing season of approximately 329 days, which is sufficient for Shiso (50-70 days to maturity).
When can I harvest Shiso in Zone 9b?
In Zone 9b, expect to harvest Shiso from March 29 – May 24. Shiso takes 50-70 days from planting to harvest.
What is the last frost date for Zone 9b?
The average last spring frost in Zone 9b is around January 25, and the first fall frost is around December 20. This gives a growing season of approximately 329 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 Free Printable Garden Planner
A 24-page printable planner tailored to your zone. Planting dates, monthly task lists, harvest log, seed inventory, and succession charts — everything you need to plan a full season.