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When to Plant Pumpkin in Harris County, TX

Harris County, Texas Zone 9b May

May in Harris County, Texas — your action list

May rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Harris County, Texas.

Avg. last frost February 14
Avg. first frost December 4
Soil temp (4") 77°F
Watering Low
Pest pressure High
Daylight 13.5 hrs
  1. Pick pumpkin

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

To set up a strong June, finish these tasks
  • First harvests: pumpkin

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Pumpkins are large-fruited squash varieties grown for eating, decoration, and seed production. They require ample space and a long, warm growing season.

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 Pumpkin may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Pumpkin will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Pumpkin 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

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (146 days to spare)
Start indoors: Jan 9 Transplant: Feb 13 🍅 Harvest: May 15 – Jul 3
Recommended (50%) ✓ Fits season (146 days to spare)
Start indoors: Jan 17 Transplant: Feb 21 🍅 Harvest: May 23 – Jul 11
Safe Start (90%) ✓ Fits season (142 days to spare)
Start indoors: Feb 8 Transplant: Mar 15 🍅 Harvest: Jun 14 – Aug 2

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 Pumpkin's growing requirements.

Soil pH

Your soil pH (5.3–6.5) is more acidic than Pumpkin 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. Pumpkin 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 Pumpkin.

How to Plant Pumpkin

1"
Planting Depth
30"
Between Plants
42"
Between Rows

Plant Water Budget

Plant needs
1.3″/week
Rainfall provides
1.0″/week
You supply
0.3″/week
Watering frequency 1-2 times/week
Season total 871 gal / 100 sq ft

Monthly Watering Guide for Pumpkin

Pumpkin needs approximately 1.3 inches of water per week (5.6" per month). Here's how your county's rainfall compares month by month.

Month Pumpkin Needs Rainfall You Supplement Action
Jan 1.6" 0" ❄️ Dormant
Feb 5.6" 2.7" 2.9" 🚿 Regular watering
Mar 5.6" 3.8" 1.8" 💧 Light watering
Apr 5.6" 7.4" 0" ✅ Rainfall sufficient
May 5.6" 10.1" 0" ✅ Rainfall sufficient
Jun 5.6" 10" 0" ✅ Rainfall sufficient
Jul 5.6" 9.6" 0" ✅ Rainfall sufficient
Aug 5.6" 8.5" 0" ✅ Rainfall sufficient
Sep 5.6" 6.3" 0" ✅ Rainfall sufficient
Oct 5.6" 3.9" 1.7" 💧 Light watering
Nov 5.6" 2.2" 3.4" 🚿 Regular watering
Dec 5.6" 1.6" 4" 🚿 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.

Pumpkin 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.

Pumpkin needs ~2,716 GDD — county provides 7,791 GDD Excellent fit

Pumpkin Planting Timeline — Harris County, TX

Pumpkin Planting Calendar

Activity When Date Range
Start Indoors January 17 Jan 17 – Jan 31
Transplant Outdoors February 21 Feb 21 – Mar 7
Direct Sow February 14 Feb 14 – Mar 7
Harvest May 23 May 23 – Jul 11

Plant 1" deep · 30" apart · Rows 42" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1.3"/week · 1-2 times/week

📅 Days to Maturity

85–120 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 Pumpkin in Harris County

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

Sandy soil in Harris County dries quickly — mulch Pumpkin 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 Pumpkin and water deeply in the morning.

Common pests for Pumpkin in this region include squash vine borer and cucumber beetles. Use row covers early in the season and inspect plants weekly.

General growing tips

Direct sow on mounds after last frost. Allow 6-10 feet between plants. Slip a board under developing fruit to prevent rot. Harvest when rind is hard and deep in color.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Pumpkin in Harris County, TX?

Harris County is in Zone 9b with an average last frost of February 14. Plan your Pumpkin 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.

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Your Harris County Garden Planner — Free

A 24-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: May 2026.

Sources & credits

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