When to Plant Radish in Cowichan Valley, BC
Radishes are one of the fastest-growing vegetables, with some varieties ready in under a month. They come in round, elongated, and large winter types.
Cowichan Valley, British Columbia is in USDA Zone 9a. The average last spring frost is March 5 and the first fall frost is November 10, giving you a growing season of approximately 250 days.
At an elevation of 147 feet, Cowichan Valley receives approximately 63.5 inches of rainfall annually with predominantly podzolic loam soil. Summer highs average 96°F, so Radish may need afternoon shade and extra watering during peak heat. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Radish root diseases.
Cowichan Valley 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 Radish
Fall planting: Sow 8 weeks before your first frost date for a fall harvest.
Plant Water Budget
Monthly Watering Guide for Radish
Radish needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.
| Month | Radish Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 2.7" | 0" | ❄️ Dormant |
| Feb | — | 2.7" | 0" | ❄️ Dormant |
| Mar | 2.2" | 4" | 0" | ✅ Rainfall sufficient |
| Apr | 2.2" | 5.9" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 8.1" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 7.9" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 6.4" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 6.3" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 5.3" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 5.9" | 0" | ✅ Rainfall sufficient |
| Nov | 2.2" | 4.5" | 0" | ✅ Rainfall sufficient |
| Dec | — | 4" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Cowichan Valley). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Radish 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.
Radish Planting Timeline — Cowichan Valley, BC
Radish Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | February 12 | Feb 12 – Mar 5 |
| Harvest | March 12 | Mar 12 – Apr 2 |
| Fall Sowing | September 15 | Sep 15 – Sep 29 |
Plant 0.5" deep · 2" apart · Rows 6" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Direct Sow |
| March | Direct Sow Harvest |
| April | Harvest |
| May | — |
| June | — |
| July | — |
| August | — |
| September | Fall Sowing |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
22–35 days
🧪 Soil pH
Needs 6–7 · Your soil: N/A
🗺️ USDA Zone
Zone 9a
📆 Growing Season
250 days in Cowichan Valley
Growing Tips for Radish in Cowichan Valley
Summer highs in Cowichan Valley reach 96°F — grow Radish as a spring or fall crop. Use shade cloth if planting in summer.
Your generous 250.0-day season in Cowichan Valley allows multiple plantings of Radish. Sow every 11.0 days for continuous harvest.
Common pests for Radish in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.
With 64" of annual rainfall in Cowichan Valley, ensure good drainage for Radish — excess moisture can promote root rot and fungal diseases.
General growing tips
Direct sow every 1-2 weeks for continuous harvest. Do not transplant. Harvest spring radishes promptly to prevent them from becoming pithy and hot.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Radish in Other Locations
Frequently Asked Questions
When should I plant Radish in Cowichan Valley, BC?
Cowichan Valley is in Zone 9a with an average last frost of March 5. Plan your Radish planting based on this frost date — see the calendar above for exact timing.
What planting zone is Cowichan Valley, BC?
Cowichan Valley, British Columbia is in USDA Hardiness Zone 9a. The average last spring frost is March 5 and first fall frost is November 10.
Your Cowichan Valley Garden Planner — Free
A 24-page printable planner built for Cowichan Valley (Zone 9a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.