When to Plant Pac Choi in Rock County, WI
May to-do list for Rock County, Wisconsin
Your Rock County, Wisconsin garden is entering a new phase. Here's what's on the schedule for May and why each task matters now.
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Start pac choi under lights
Give them 6–8 weeks indoors before the last frost and you'll transplant into warm soil with seedlings that are already leaping.
A few tasks this May that'll pay off in June
- First harvests: pac choi
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.
Rock County, Wisconsin is in USDA Zone 5b. The average last spring frost is April 26 and the first fall frost is October 13, giving you a growing season of approximately 170 days.
At an elevation of 710 feet, Rock County receives approximately 30.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Pac Choi during the growing season.
Rock County Soil Profile
Soil Type
Silt Loam
Soil pH
6.2-7.1
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.
Soil Compatibility in Rock County
How your county's soil matches Pac Choi's growing requirements.
Soil pH
Your soil pH (6.2–7.1) is within Pac Choi's preferred range (6.0–7.5).
Soil Texture
The silt loam soil in Rock County is excellent for Pac Choi — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (5.1%) — Pac Choi will thrive.
How to Plant Pac Choi
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Pac Choi
Sow every 4.6 weeks. Last sowing by Aug 19 to harvest before frost.
For a dedicated fall crop, sow by Aug 04.
Plant Water Budget
Water stress score is 6/10 — 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 | — | 1.3" | 0" | ❄️ Dormant |
| Feb | — | 1.4" | 0" | ❄️ Dormant |
| Mar | — | 2.1" | 0" | ❄️ Dormant |
| Apr | 6.5" | 3.3" | 3.2" | 💧 Light watering |
| May | 6.5" | 3.1" | 3.4" | 🚿 Regular watering |
| Jun | 6.5" | 3.8" | 2.7" | 💧 Light watering |
| Jul | 6.5" | 3.2" | 3.3" | 🚿 Regular watering |
| Aug | 6.5" | 3" | 3.5" | 🚿 Regular watering |
| Sep | 6.5" | 2.8" | 3.7" | 🚿 Regular watering |
| Oct | 6.5" | 2.6" | 3.9" | 🚿 Regular watering |
| Nov | — | 2.4" | 0" | ❄️ Dormant |
| Dec | — | 1.5" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Rock 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 Planting Timeline — Rock County, WI
Pac Choi Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 22 | Mar 22 – Apr 5 |
| Transplant Outdoors | April 26 | Apr 26 – May 10 |
| Direct Sow | April 12 | Apr 12 – May 3 |
| Harvest | June 7 | Jun 7 – Jul 5 |
| Fall Sowing | August 4 | Aug 4 – Aug 18 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | Harvest |
| July | Harvest |
| August | Fall Sowing |
| September | — |
| October | — |
| November | — |
| December | — |
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 5b
📆 Growing Season
170 days in Rock County
Growing Tips for Pac Choi in Rock County
Direct sow Pac Choi outdoors after April 26 in Rock County when soil has warmed and frost danger has passed.
Your generous 170.0-day season in Rock County allows multiple plantings of Pac Choi. Sow every 20.0 days for continuous harvest.
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
Check more plant combinations with our Companion Planting Checker →
Pac Choi in Other Locations
Frequently Asked Questions
When should I plant Pac Choi in Rock County, WI?
Rock County is in Zone 5b with an average last frost of April 26. Plan your Pac Choi planting based on this frost date — see the calendar above for exact timing.
What planting zone is Rock County, WI?
Rock County, Wisconsin is in USDA Hardiness Zone 5b. The average last spring frost is April 26 and first fall frost is October 13.
Your Rock County Garden Planner — Free
A 24-page printable planner built for Rock County (Zone 5b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.