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When to Plant Pac Choi in Harris County, TX

Harris County, Texas Zone 9b August

This month in Harris County, Texas

If you only do a handful of things in the garden this August, make it these. They're sequenced around your zone's frost timing.

Avg. last frost February 14
Avg. first frost December 4
Soil temp (4") 96°F
Watering Low
Pest pressure High
Daylight 13.1 hrs

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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.

Harris County, Texas is in USDA Zone 9b. The average last spring frost is February 14 and the first fall frost is December 4, giving you a growing season of approximately 293 days.

At an elevation of 390 feet, Harris County receives approximately 67.7 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 102°F, so Pac Choi may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Pac Choi will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Pac Choi root diseases.

Harris County, TX (Zone 9b) Year-round
293 days
Last Spring Frost February 14
293 growing days
First Fall Frost December 4

Harris County Soil Profile

Soil Type

Sandy Loam

Soil pH

5.3-6.5

Drainage

Well Drained

Pac Choi Planting Risk Windows

Early Start (70% safe) ✓ Fits season (223 days to spare)
Start indoors: Jan 9 Transplant: Feb 6 🍅 Harvest: Mar 20 – Apr 17
Recommended (50%) ✓ Fits season (223 days to spare)
Start indoors: Jan 17 Transplant: Feb 14 🍅 Harvest: Mar 28 – Apr 25
Safe Start (90%) ✓ Fits season (219 days to spare)
Start indoors: Feb 8 Transplant: Mar 8 🍅 Harvest: Apr 19 – May 17

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 Harris County

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

Soil pH

Your soil pH (5.3–6.5) is more acidic than Pac Choi prefers (6.0–7.5). Add garden lime to raise pH.

Soil Texture

Sandy soil in Harris County warms quickly in spring but drains fast. Pac Choi will need more frequent watering and regular compost additions to retain nutrients.

Organic Matter

Organic matter is moderate (2.2%). Annual compost additions will help Pac Choi.

How to Plant Pac Choi

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

Fall planting: Sow 8 weeks before your first frost date for a fall harvest.

Succession Planting Pac Choi

8
successive plantings in your 293-day season

Sow every 4.6 weeks. Last sowing by Oct 10 to harvest before frost.

For a dedicated fall crop, sow by Oct 09.

Pac Choi Water Budget

Plant needs
1.5″/week
Rainfall provides
1.0″/week
You supply
0.5″/week
Watering frequency 1-2 times/week
Season total 1,394 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 1.6" 0" ❄️ Dormant
Feb 6.5" 2.7" 3.8" 🚿 Regular watering
Mar 6.5" 3.8" 2.7" 💧 Light watering
Apr 6.5" 7.4" 0" ✅ Rainfall sufficient
May 6.5" 10.1" 0" ✅ Rainfall sufficient
Jun 6.5" 10" 0" ✅ Rainfall sufficient
Jul 6.5" 9.6" 0" ✅ Rainfall sufficient
Aug 6.5" 8.5" 0" ✅ Rainfall sufficient
Sep 6.5" 6.3" 0.2" 💧 Light watering
Oct 6.5" 3.9" 2.6" 💧 Light watering
Nov 6.5" 2.2" 4.3" 🚿 Regular watering
Dec 6.5" 1.6" 4.9" 🚿 Regular watering

Water needs are for active growing months only (Feb–Dec in Harris 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 ~1,259 GDD — county provides 7,791 GDD Excellent fit

Pac Choi Planting Timeline — Harris County, TX

Pac Choi Planting Calendar

Activity When Date Range
Start Indoors January 17 Jan 17 – Jan 31
Transplant Outdoors February 14 Feb 14 – Feb 28
Direct Sow January 24 Jan 24 – Feb 14
Harvest March 28 Mar 28 – Apr 25
Fall Sowing October 9 Oct 9 – Oct 23

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1.5"/week · 1-2 times/week

📅 Days to Maturity

40–55 days

🧪 Soil pH

Needs 6–7.5 · Your soil: too_acidic

🗺️ USDA Zone

Zone 9b

📆 Growing Season

293 days in Harris County

Growing Tips for Pac Choi in Harris County

Direct sow Pac Choi outdoors after February 14 in Harris County when soil has warmed and frost danger has passed.

Sandy soil in Harris County dries quickly — mulch Pac Choi with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

With summer highs reaching 102°F in Harris County, provide afternoon shade for Pac Choi and water deeply in the morning.

Your generous 294.0-day season in Harris 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 Harris County, TX?

Harris County is in Zone 9b with an average last frost of February 14. Plan your Pac Choi planting based on this frost date — see the calendar above for exact timing.

What planting zone is Harris County, TX?

Harris County, Texas is in USDA Hardiness Zone 9b. The average last spring frost is February 14 and first fall frost is December 4.

🌱

Your Harris County Garden Planner — Free

A 22-page printable planner built for Harris County (Zone 9b). 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 Harris County, TX. Local conditions may vary. Last updated: August 2026.

Sources & credits

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