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When to Plant Pac Choi in Alpena County, MI

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.

Alpena County, Michigan is in USDA Zone 5a. The average last spring frost is May 19 and the first fall frost is October 3, giving you a growing season of approximately 137 days.

At an elevation of 984 feet, Alpena County receives approximately 31.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86ยฐF, providing good warmth for Pac Choi during the growing season.

Alpena County, MI (Zone 5a) Short season
137 days
Last Spring Frost May 19
137 growing days
First Fall Frost October 3

Alpena County Soil Profile

Soil Type

Silt Loam

Soil pH

6-7.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (69 days to spare)
Start indoors: Apr 8 Transplant: May 13 🍅 Harvest: Jun 24 – Jul 22
Recommended (50%) ✓ Fits season (67 days to spare)
Start indoors: Apr 14 Transplant: May 19 🍅 Harvest: Jun 30 – Jul 28
Safe Start (90%) ✓ Fits season (74 days to spare)
Start indoors: Apr 25 Transplant: May 30 🍅 Harvest: Jul 11 – Aug 8

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 Alpena County

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

Soil pH

Your soil pH (6.0โ€“7.3) is within Pac Choi's preferred range (6.0โ€“7.5).

Soil Texture

The silt loam soil in Alpena County is excellent for Pac Choi โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is excellent (4.3%) โ€” Pac Choi will thrive.

How to Plant Pac Choi

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

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Pac Choi

4
successive plantings in your 137-day season

Sow every 4.6 weeks. Last sowing by Aug 09 to harvest before frost.

For a dedicated fall crop, sow by Jul 25.

Plant Water Budget

Plant needs
1.5″/week
Rainfall provides
1.0″/week
You supply
0.7″/week
Watering frequency 1-2 times/week
Season total 800 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” 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 โ€” 1.3" 0" โ„๏ธ Dormant
Feb โ€” 1.5" 0" โ„๏ธ Dormant
Mar โ€” 2.2" 0" โ„๏ธ Dormant
Apr โ€” 3.3" 0" โ„๏ธ Dormant
May 6.5" 3.4" 3.1" ๐Ÿ’ง Light watering
Jun 6.5" 3.5" 3" ๐Ÿ’ง Light watering
Jul 6.5" 3.4" 3.1" ๐Ÿ’ง Light watering
Aug 6.5" 2.9" 3.6" ๐Ÿšฟ Regular watering
Sep 6.5" 3" 3.5" ๐Ÿšฟ Regular watering
Oct 6.5" 2.2" 4.3" ๐Ÿšฟ Regular watering
Nov โ€” 2.3" 0" โ„๏ธ Dormant
Dec โ€” 2" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Mayโ€“Oct in Alpena County). Supplement amounts are based on average rainfall โ€” 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" โ€” every day above 50ยฐF 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 ~689 GDD — county provides 1,986 GDD Excellent fit

Pac Choi Planting Timeline โ€” Alpena County, MI

Pac Choi Planting Calendar

Activity When Date Range
Start Indoors April 14 Apr 14 โ€“ Apr 28
Transplant Outdoors May 19 May 19 โ€“ Jun 2
Direct Sow May 5 May 5 โ€“ May 26
Harvest June 30 Jun 30 โ€“ Jul 28
Fall Sowing July 25 Jul 25 โ€“ Aug 8

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

1.5"/week ยท 1-2 times/week

๐Ÿ“… Days to Maturity

40โ€“55 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: ideal

๐Ÿ—บ๏ธ USDA Zone

Zone 5a

๐Ÿ“† Growing Season

137 days in Alpena County

Growing Tips for Pac Choi in Alpena County

Direct sow Pac Choi outdoors after May 19 in Alpena 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 Alpena County, MI?

Alpena County is in Zone 5a with an average last frost of May 19. Plan your Pac Choi planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Alpena County, MI?

Alpena County, Michigan is in USDA Hardiness Zone 5a. The average last spring frost is May 19 and first fall frost is October 3.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Alpena County gardeners in Zone 5a organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

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