When to Plant Komatsuna in North Coast, BC
Komatsuna (Japanese mustard spinach) is a versatile Asian green with glossy, dark leaves and a mild, sweet flavor. It is extremely cold-hardy and heat-tolerant.
North Coast, British Columbia is in USDA Zone 8a. The average last spring frost is April 6 and the first fall frost is November 12, giving you a growing season of approximately 220 days.
At an elevation of 114 feet, North Coast receives approximately 55.9 inches of rainfall annually with predominantly podzolic loam soil. Summer highs average 91°F, providing good warmth for Komatsuna during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Komatsuna root diseases.
North Coast Soil Profile
Soil Type
Podzolic Loam
Soil pH
6.0-7.0
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.
How to Plant Komatsuna
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Plant Water Budget
Monthly Watering Guide for Komatsuna
Komatsuna needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Komatsuna Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 2.1" | 0" | ❄️ Dormant |
| Feb | — | 2.8" | 0" | ❄️ Dormant |
| Mar | — | 3.4" | 0" | ❄️ Dormant |
| Apr | 4.3" | 5.2" | 0" | ✅ Rainfall sufficient |
| May | 4.3" | 7.2" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 7.5" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 6.3" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 5.7" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 5.1" | 0" | ✅ Rainfall sufficient |
| Oct | 4.3" | 4" | 0.3" | 💧 Light watering |
| Nov | 4.3" | 3.7" | 0.6" | 💧 Light watering |
| Dec | — | 2.9" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Nov in North Coast). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Komatsuna 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.
Komatsuna Planting Timeline — North Coast, BC
Komatsuna Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 2 | Mar 2 – Mar 16 |
| Transplant Outdoors | April 6 | Apr 6 – Apr 20 |
| Direct Sow | March 23 | Mar 23 – Apr 13 |
| Harvest | May 11 | May 11 – Jun 15 |
| Fall Sowing | September 3 | Sep 3 – Sep 17 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | Harvest |
| June | Harvest |
| July | — |
| August | — |
| September | Fall Sowing |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
1"/week · Natural rainfall sufficient
📅 Days to Maturity
35–50 days
🧪 Soil pH
Needs 6–7.5 · Your soil: N/A
🗺️ USDA Zone
Zone 8a
📆 Growing Season
220 days in North Coast
Growing Tips for Komatsuna in North Coast
Your generous 219.0-day season in North Coast allows multiple plantings of Komatsuna. Sow every 17.0 days for continuous harvest.
Common pests for Komatsuna in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.
General growing tips
Direct sow in spring or fall. One of the most forgiving Asian greens for all seasons. Harvest outer leaves or cut whole plants. Excellent for stir-fries, soups, or salads.
Companion Planting
Good Companions
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Check more plant combinations with our Companion Planting Checker →
Komatsuna in Other Locations
Frequently Asked Questions
When should I plant Komatsuna in North Coast, BC?
North Coast is in Zone 8a with an average last frost of April 6. Plan your Komatsuna planting based on this frost date — see the calendar above for exact timing.
What planting zone is North Coast, BC?
North Coast, British Columbia is in USDA Hardiness Zone 8a. The average last spring frost is April 6 and first fall frost is November 12.
Your North Coast Garden Planner — Free
A 24-page printable planner built for North Coast (Zone 8a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.