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When to Plant Kai Lan in Jasper County, TX

Jasper County, Texas Zone 9a May

Your May gardening checklist

Welcome to May in Zone 9a. These are the moves that will have the biggest impact on your growing season.

Avg. last frost March 3
Avg. first frost November 22
Soil temp (4") 73°F
Watering Low
Pest pressure High
Daylight 13.6 hrs
  1. It's harvest week for kai lan

    The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.

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Kai lan (Chinese broccoli) is a brassica grown for its thick, glossy stems and small flower buds. It has a slightly bitter, broccoli-like flavor essential in Cantonese cooking.

Jasper County, Texas is in USDA Zone 9a. The average last spring frost is March 3 and the first fall frost is November 22, giving you a growing season of approximately 264 days.

At an elevation of 97 feet, Jasper County receives approximately 71.8 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 97°F, so Kai Lan may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Kai Lan will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Kai Lan root diseases.

Jasper County, TX (Zone 9a) Long season
264 days
Last Spring Frost March 3
264 growing days
First Fall Frost November 22
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Jasper County Soil Profile

Soil Type

Sandy Loam

Soil pH

5.3-6.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (193 days to spare)
Start indoors: Jan 20 Transplant: Feb 17 🍅 Harvest: Apr 7 – May 5
Recommended (50%) ✓ Fits season (187 days to spare)
Start indoors: Feb 3 Transplant: Mar 3 🍅 Harvest: Apr 21 – May 19
Safe Start (90%) ✓ Fits season (182 days to spare)
Start indoors: Feb 28 Transplant: Mar 28 🍅 Harvest: May 16 – Jun 13

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 Jasper County

How your county's soil matches Kai Lan's growing requirements.

Soil pH

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

Soil Texture

Sandy soil in Jasper County warms quickly in spring but drains fast. Kai Lan will need more frequent watering and regular compost additions to retain nutrients.

Organic Matter

Organic matter is low (1.7%). Add 2-3 inches of compost before planting Kai Lan.

How to Plant Kai Lan

0.5"
Planting Depth
6"
Between Plants
12"
Between Rows

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

Succession Planting Kai Lan

7
successive plantings in your 264-day season

Sow every 5.1 weeks. Last sowing by Sep 23 to harvest before frost.

For a dedicated fall crop, sow by Sep 27.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.1″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Kai Lan

Kai Lan needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Kai Lan Needs Rainfall You Supplement Action
Jan 1.6" 0" ❄️ Dormant
Feb 2.7" 0" ❄️ Dormant
Mar 4.3" 4.2" 0.1" 💧 Light watering
Apr 4.3" 7.3" 0" ✅ Rainfall sufficient
May 4.3" 10.8" 0" ✅ Rainfall sufficient
Jun 4.3" 12.7" 0" ✅ Rainfall sufficient
Jul 4.3" 7.8" 0" ✅ Rainfall sufficient
Aug 4.3" 8.4" 0" ✅ Rainfall sufficient
Sep 4.3" 7.2" 0" ✅ Rainfall sufficient
Oct 4.3" 4.9" 0" ✅ Rainfall sufficient
Nov 4.3" 2.3" 2" 💧 Light watering
Dec 1.8" 0" ❄️ Dormant

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

Kai Lan 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.

Kai Lan needs ~1,194 GDD — county provides 6,006 GDD Excellent fit

Kai Lan Planting Timeline — Jasper County, TX

Kai Lan Planting Calendar

Activity When Date Range
Start Indoors February 3 Feb 3 – Feb 17
Transplant Outdoors March 3 Mar 3 – Mar 17
Direct Sow February 10 Feb 10 – Mar 3
Harvest April 21 Apr 21 – May 19
Fall Sowing September 27 Sep 27 – Oct 11

Plant 0.5" deep · 6" apart · Rows 12" apart

Month-by-Month Timeline

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

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Natural rainfall sufficient

📅 Days to Maturity

45–60 days

🧪 Soil pH

Needs 6–7.5 · Your soil: too_acidic

🗺️ USDA Zone

Zone 9a

📆 Growing Season

264 days in Jasper County

Growing Tips for Kai Lan in Jasper County

Direct sow Kai Lan outdoors after March 03 in Jasper County when soil has warmed and frost danger has passed.

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

With summer highs reaching 97°F in Jasper County, provide afternoon shade for Kai Lan and water deeply in the morning.

Your generous 264.0-day season in Jasper County allows multiple plantings of Kai Lan. Sow every 22.0 days for continuous harvest.

Common pests for Kai Lan 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. Harvest when flower buds first appear but before they open. Cut stems at the base to encourage side shoots. Prefers cool weather.

Companion Planting

Good Companions

Avoid Planting Near

  • Strawberries

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Kai Lan in Jasper County, TX?

Jasper County is in Zone 9a with an average last frost of March 3. Plan your Kai Lan planting based on this frost date — see the calendar above for exact timing.

What planting zone is Jasper County, TX?

Jasper County, Texas is in USDA Hardiness Zone 9a. The average last spring frost is March 3 and first fall frost is November 22.

🌱

Your Jasper County Garden Planner — Free

A 24-page printable planner built for Jasper County (Zone 9a). 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 Jasper County, TX. 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.