When to plant Bok Choy in Mahnomen County, MN
Mahnomen County gardeners should plant Bok Choy between May 6 and May 27 in spring. With Mahnomen County's Zone 4a climate (last frost May 13), Bok Choy needs 40–60 days to mature — plant by July 29 for a full harvest. A second sowing from July 5 to July 19 extends the harvest into fall.
When to Plant Bok Choy in Mahnomen County, MN
What to do in June
Welcome to June in Zone 4a. These are the moves that will have the biggest impact on your growing season.
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.
Mahnomen County, Minnesota is in USDA Zone 4a. The average last spring frost is May 13 and the first fall frost is September 27, giving you a growing season of approximately 137 days.
At an elevation of 1,223 feet, Mahnomen County receives approximately 33.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 80°F, so choose short-season varieties of Bok Choy to ensure they mature before fall.
Mahnomen County Soil Profile
Soil Type
Silt Loam
Soil pH
5.9-7
Drainage
Well Drained
Bok Choy 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.
Soil Compatibility in Mahnomen County
How your county's soil matches Bok Choy's growing requirements.
Soil pH
Your soil pH (5.9–7.0) overlaps with Bok Choy's range (6.0–7.5), though not a perfect match.
Soil Texture
The silt loam soil in Mahnomen County is excellent for Bok Choy — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Bok Choy is a heavy drinker but your soil drains very quickly. Mulch heavily and consider drip irrigation.
Organic Matter
Organic matter is excellent (4.0%) — Bok Choy will thrive.
How to Plant Bok Choy
Fall planting: Sow 12 weeks before your first frost date for a fall harvest.
Succession Planting Bok Choy
Sow every 4.6 weeks. Last sowing by Jul 29 to harvest before frost.
For a dedicated fall crop, sow by Jul 05.
Bok Choy 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 | — | 1.3" | 0" | ❄️ Dormant |
| Feb | — | 1.5" | 0" | ❄️ Dormant |
| Mar | — | 2.2" | 0" | ❄️ Dormant |
| Apr | — | 2.9" | 0" | ❄️ Dormant |
| May | 3" | 4.3" | 0" | ✅ Rainfall sufficient |
| Jun | 3" | 3.8" | 0" | ✅ Rainfall sufficient |
| Jul | 3" | 3.7" | 0" | ✅ Rainfall sufficient |
| Aug | 3" | 3.6" | 0" | ✅ Rainfall sufficient |
| Sep | 3" | 3.1" | 0" | ✅ Rainfall sufficient |
| Oct | — | 2.4" | 0" | ❄️ Dormant |
| Nov | — | 2.4" | 0" | ❄️ Dormant |
| Dec | — | 2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Mahnomen County). 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 — Mahnomen County, MN
Bok Choy Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 1 | Apr 1 – Apr 15 |
| Transplant Outdoors | May 13 | May 13 – May 27 |
| Direct Sow | May 6 | May 6 – May 27 |
| Harvest | June 24 | Jun 24 – Jul 29 |
| Fall Sowing | July 5 | Jul 5 – Jul 19 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| 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 · Natural rainfall sufficient
📅 Days to Maturity
40–60 days
🧪 Soil pH
Needs 6–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 4a
📆 Growing Season
137 days in Mahnomen County
Growing Tips for Bok Choy in Mahnomen County
Direct sow Bok Choy outdoors after May 13 in Mahnomen County when soil has warmed and frost danger has passed.
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
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Bok Choy in Other Locations
Frequently Asked Questions
When should I plant Bok Choy in Mahnomen County, MN?
Mahnomen County is in Zone 4a with an average last frost of May 13. Plan your Bok Choy planting based on this frost date — see the calendar above for exact timing.
What planting zone is Mahnomen County, MN?
Mahnomen County, Minnesota is in USDA Hardiness Zone 4a. The average last spring frost is May 13 and first fall frost is September 27.
When should I plant Bok Choy in Mahnomen County, MN?
In Mahnomen County, MN, plant Bok Choy after the last frost (around May 13) and before the first frost (around September 27). Best results when soil holds above 50°F.
What growing zone is Mahnomen County, MN for Bok Choy?
Mahnomen County sits in USDA Zone 4a. Bok Choy grows reliably in zones 2a through 11b, so it's a good fit here.
Can Bok Choy grow in Mahnomen County's climate?
Yes — Bok Choy grows well in Mahnomen County's temperate climate. Mahnomen County averages a 137-day frost-free season, with last frost around May 13 and first frost around September 27.
Your Mahnomen County Garden Planner — Free
A 22-page printable planner built for Mahnomen County (Zone 4a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.