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When to Plant Pac Choi in Mountrail County, ND

Mountrail County, North Dakota Zone 4a May

Your May planting checklist for Mountrail County, North Dakota

Your Mountrail County, North Dakota garden is entering a new phase. Here's what's on the schedule for May and why each task matters now.

Avg. last frost May 17
Avg. first frost September 22
Soil temp (4") 50°F
Watering Moderate
Pest pressure Low
Daylight 15 hrs
  1. Plant out pac choi

    Pick a cloudy afternoon or evening to plant. Less transplant shock, and your seedlings will barely blink.

  2. Scatter pac choi into prepared beds

    These tolerate cool soil, so you're not gambling by sowing now.

To set up a strong June, finish these tasks
  • Starting indoors: pac choi
  • First harvests: pac choi
  • Fall sowing: pac choi

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Pac choi (baby bok choy) is a compact variety of Chinese cabbage with tender leaves and crisp stems. It grows quickly and is ideal for containers and small spaces.

Mountrail County, North Dakota is in USDA Zone 4a. The average last spring frost is May 17 and the first fall frost is September 22, giving you a growing season of approximately 128 days.

At an elevation of 1,059 feet, Mountrail County receives approximately 26.2 inches of rainfall annually with predominantly loam soil. Summer highs average 78°F, so choose short-season varieties of Pac Choi to ensure they mature before fall.

Mountrail County, ND (Zone 4a) Short season
128 days
Last Spring Frost May 17
128 growing days
First Fall Frost September 22
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Mountrail County Soil Profile

Soil Type

Loam

Soil pH

6.8-7.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (59 days to spare)
Start indoors: Mar 31 Transplant: May 12 🍅 Harvest: Jun 23 – Jul 21
Recommended (50%) ✓ Fits season (58 days to spare)
Start indoors: Apr 5 Transplant: May 17 🍅 Harvest: Jun 28 – Jul 26
Safe Start (90%) ✓ Fits season (60 days to spare)
Start indoors: Apr 17 Transplant: May 29 🍅 Harvest: Jul 10 – Aug 7

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 Mountrail County

How your county's soil matches Pac Choi's growing requirements.

Soil pH

Your soil pH (6.8–7.5) is within Pac Choi's preferred range (6.0–7.5).

Soil Texture

The loam soil in Mountrail County is excellent for Pac Choi — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is excellent (4.3%) — Pac Choi will thrive.

How to Plant Pac Choi

1"
Planting Depth
15"
Between Plants
24"
Between Rows

Fall planting: Sow 12 weeks before your first frost date for a fall harvest.

Succession Planting Pac Choi

3
successive plantings in your 128-day season

Sow every 4.6 weeks. Last sowing by Jul 29 to harvest before frost.

For a dedicated fall crop, sow by Jun 30.

Plant Water Budget

Plant needs
1.5″/week
Rainfall provides
0.9″/week
You supply
0.8″/week
Watering frequency 2-3 times/week
Season total 875 gal / 100 sq ft
Drought risk

Water stress score is 8/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Pac Choi

Pac Choi needs approximately 1.5 inches of water per week (6.5" per month). Here's how your county's rainfall compares month by month.

Month Pac Choi Needs Rainfall You Supplement Action
Jan 2" 0" ❄️ Dormant
Feb 1.5" 0" ❄️ Dormant
Mar 2.6" 0" ❄️ Dormant
Apr 3" 0" ❄️ Dormant
May 6.5" 2.9" 3.6" 🚿 Regular watering
Jun 6.5" 1.7" 4.8" 🚿 Regular watering
Jul 6.5" 2.1" 4.4" 🚿 Regular watering
Aug 6.5" 2.7" 3.8" 🚿 Regular watering
Sep 6.5" 2.2" 4.3" 🚿 Regular watering
Oct 2.5" 0" ❄️ Dormant
Nov 1.6" 0" ❄️ Dormant
Dec 1.4" 0" ❄️ Dormant

Water needs are for active growing months only (May–Sep in Mountrail County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Pac Choi 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.

Pac Choi needs ~404 GDD — county provides 1,088 GDD Excellent fit

Pac Choi Planting Timeline — Mountrail County, ND

Pac Choi Planting Calendar

Activity When Date Range
Start Indoors April 5 Apr 5 – Apr 19
Transplant Outdoors May 17 May 17 – May 31
Direct Sow May 10 May 10 – May 31
Harvest June 28 Jun 28 – Jul 26
Fall Sowing June 30 Jun 30 – Jul 14

Plant 1" deep · 15" apart · Rows 24" apart

Month-by-Month Timeline

MonthActivities
January
February
March
April Start Indoors
May Transplant Outdoors Direct Sow
June Fall Sowing Harvest
July Fall Sowing Harvest
August
September
October
November
December
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Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1.5"/week · 2-3 times/week

📅 Days to Maturity

40–55 days

🧪 Soil pH

Needs 6–7.5 · Your soil: ideal

🗺️ USDA Zone

Zone 4a

📆 Growing Season

128 days in Mountrail County

Growing Tips for Pac Choi in Mountrail County

Direct sow Pac Choi outdoors after May 17 in Mountrail County when soil has warmed and frost danger has passed.

Common pests for Pac Choi 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. Grows best in cool weather. Space 6 inches apart for baby pac choi. Harvest whole plants or cut outer leaves as needed.

Companion Planting

Good Companions

Avoid Planting Near

  • Strawberries

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Pac Choi in Mountrail County, ND?

Mountrail County is in Zone 4a with an average last frost of May 17. Plan your Pac Choi planting based on this frost date — see the calendar above for exact timing.

What planting zone is Mountrail County, ND?

Mountrail County, North Dakota is in USDA Hardiness Zone 4a. The average last spring frost is May 17 and first fall frost is September 22.

🌱

Your Mountrail County Garden Planner — Free

A 24-page printable planner built for Mountrail 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.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Mountrail County, ND. Local conditions may vary. Last updated: May 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.