When to Plant Bok Choy in Stettler, AB
Bok choy is a Chinese cabbage variety with crisp white stalks and dark green leaves. It is a fast-growing cool-season crop ideal for stir-fries and soups.
Stettler, Alberta is in USDA Zone 4b. The average last spring frost is May 11 and the first fall frost is October 5, giving you a growing season of approximately 147 days.
At an elevation of 2,598 feet, Stettler receives approximately 18.3 inches of rainfall annually with predominantly dark brown chernozem soil. Summer highs average 74°F, so choose short-season varieties of Bok Choy to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Bok Choy successfully. Mulch heavily to conserve soil moisture.
Stettler Soil Profile
Soil Type
Dark Brown Chernozem
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 Bok Choy
Fall planting: Sow 12 weeks before your first frost date for a fall harvest.
Plant Water Budget
Monthly Watering Guide for Bok Choy
Bok Choy needs approximately 0.7 inches of water per week (3" per month). Here's how your county's rainfall compares month by month.
| Month | Bok Choy Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 0.7" | 0" | ❄️ Dormant |
| Feb | — | 0.7" | 0" | ❄️ Dormant |
| Mar | — | 1.3" | 0" | ❄️ Dormant |
| Apr | — | 1.9" | 0" | ❄️ Dormant |
| May | 3" | 2" | 1" | 💧 Light watering |
| Jun | 3" | 2.4" | 0.6" | 💧 Light watering |
| Jul | 3" | 2.3" | 0.7" | 💧 Light watering |
| Aug | 3" | 1.8" | 1.2" | 💧 Light watering |
| Sep | 3" | 1.7" | 1.3" | 💧 Light watering |
| Oct | 3" | 1.5" | 1.5" | 🚿 Regular watering |
| Nov | — | 1.1" | 0" | ❄️ Dormant |
| Dec | — | 1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Oct in Stettler). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Bok Choy 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.
Bok Choy Planting Timeline — Stettler, AB
Bok Choy Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 30 | Mar 30 – Apr 13 |
| Transplant Outdoors | May 11 | May 11 – May 25 |
| Direct Sow | May 4 | May 4 – May 25 |
| Harvest | June 22 | Jun 22 – Jul 27 |
| Fall Sowing | July 13 | Jul 13 – Jul 27 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors |
| May | Transplant Outdoors Direct Sow |
| June | Harvest |
| July | Fall Sowing Harvest |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
0.7"/week · Only during dry spells
📅 Days to Maturity
40–60 days
🧪 Soil pH
Needs 6–7.5 · Your soil: N/A
🗺️ USDA Zone
Zone 4b
📆 Growing Season
147 days in Stettler
Growing Tips for Bok Choy in Stettler
Common pests for Bok Choy 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 for best results. Keep soil consistently moist. Harvest whole heads or cut outer leaves for a cut-and-come-again approach.
Companion Planting
Good Companions
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Bok Choy in Other Locations
Frequently Asked Questions
When should I plant Bok Choy in Stettler, AB?
Stettler is in Zone 4b with an average last frost of May 11. Plan your Bok Choy planting based on this frost date — see the calendar above for exact timing.
What planting zone is Stettler, AB?
Stettler, Alberta is in USDA Hardiness Zone 4b. The average last spring frost is May 11 and first fall frost is October 5.
Plan Your Garden with Confidence
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