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When to Plant Pac Choi in Davis County, IA

Davis County, Iowa Zone 5b May

May in Davis County, Iowa — your action list

Here's what deserves your attention in Davis County, Iowa this month. Everything below is tailored to Zone 5b and timed around your local frost dates.

Avg. last frost April 19
Avg. first frost October 16
Soil temp (4") 60°F
Watering Moderate
Pest pressure Low
Daylight 14.3 hrs
  1. Sow pac choi in trays indoors

    Bottom-water once the first true leaves appear — it keeps stems dry and knocks back damping-off.

  2. It's harvest week for pac choi

    If you can't use it all right away, check the food-preservation section of your planner.

Before June arrives, get these ready
  • First harvests: 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.

Davis County, Iowa is in USDA Zone 5b. The average last spring frost is April 19 and the first fall frost is October 16, giving you a growing season of approximately 180 days.

At an elevation of 859 feet, Davis County receives approximately 30.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Pac Choi during the growing season.

Davis County, IA (Zone 5b) Moderate season
180 days
Last Spring Frost April 19
180 growing days
First Fall Frost October 16
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Davis County Soil Profile

Soil Type

Silt Loam

Soil pH

6.2-6.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (110 days to spare)
Start indoors: Mar 9 Transplant: Apr 13 🍅 Harvest: May 25 – Jun 22
Recommended (50%) ✓ Fits season (110 days to spare)
Start indoors: Mar 15 Transplant: Apr 19 🍅 Harvest: May 31 – Jun 28
Safe Start (90%) ✓ Fits season (108 days to spare)
Start indoors: Mar 29 Transplant: May 3 🍅 Harvest: Jun 14 – Jul 12

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 Davis County

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

Soil pH

Your soil pH (6.2–6.7) is within Pac Choi's preferred range (6.0–7.5).

Soil Texture

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

Organic Matter

Organic matter is excellent (4.7%) — 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

5
successive plantings in your 180-day season

Sow every 4.6 weeks. Last sowing by Aug 22 to harvest before frost.

For a dedicated fall crop, sow by Aug 07.

Plant Water Budget

Plant needs
1.5″/week
Rainfall provides
0.7″/week
You supply
0.8″/week
Watering frequency 2-3 times/week
Season total 1,270 gal / 100 sq ft

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 2.3" 0" ❄️ Dormant
Apr 6.5" 2.9" 3.6" 🚿 Regular watering
May 6.5" 3.7" 2.8" 💧 Light watering
Jun 6.5" 4" 2.5" 💧 Light watering
Jul 6.5" 3.6" 2.9" 💧 Light watering
Aug 6.5" 2.6" 3.9" 🚿 Regular watering
Sep 6.5" 2.3" 4.2" 🚿 Regular watering
Oct 6.5" 2.5" 4" 🚿 Regular watering
Nov 2.2" 0" ❄️ Dormant
Dec 1.5" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Davis 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 ~653 GDD — county provides 2,475 GDD Excellent fit

Pac Choi Planting Timeline — Davis County, IA

Pac Choi Planting Calendar

Activity When Date Range
Start Indoors March 15 Mar 15 – Mar 29
Transplant Outdoors April 19 Apr 19 – May 3
Direct Sow April 5 Apr 5 – Apr 26
Harvest May 31 May 31 – Jun 28
Fall Sowing August 7 Aug 7 – Aug 21

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

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April Transplant Outdoors Direct Sow
May Transplant Outdoors Harvest
June Harvest
July
August Fall Sowing
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 5b

📆 Growing Season

180 days in Davis County

Growing Tips for Pac Choi in Davis County

Direct sow Pac Choi outdoors after April 19 in Davis County when soil has warmed and frost danger has passed.

Your generous 180.0-day season in Davis 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

  • Strawberries

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Pac Choi in Davis County, IA?

Davis County is in Zone 5b with an average last frost of April 19. Plan your Pac Choi planting based on this frost date — see the calendar above for exact timing.

What planting zone is Davis County, IA?

Davis County, Iowa is in USDA Hardiness Zone 5b. The average last spring frost is April 19 and first fall frost is October 16.

🌱

Your Davis County Garden Planner — Free

A 24-page printable planner built for Davis 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.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Davis County, IA. 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.