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When to Plant Corn in Webb County, TX

Webb County, Texas Zone 9b May

May to-do list for Webb County, Texas

Your Webb County, Texas garden is entering a new phase. Here's what's on the schedule for May and why each task matters now.

Avg. last frost February 9
Avg. first frost December 9
Soil temp (4") 70°F
Watering Low
Pest pressure High
Daylight 13.4 hrs
  1. Harvest corn as they ripen

    Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.

Coming up in June — start thinking about
  • First harvests: corn

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Corn is a warm-season grass grown for its sweet ears, which are best eaten soon after harvest. It is wind-pollinated and must be planted in blocks for good kernel fill.

Webb County, Texas is in USDA Zone 9b. The average last spring frost is February 9 and the first fall frost is December 9, giving you a growing season of approximately 303 days.

At an elevation of 3,543 feet, Webb County receives approximately 50.9 inches of rainfall annually with predominantly loam soil. Summer highs average 95°F, so Corn may need afternoon shade and extra watering during peak heat. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Corn root diseases.

Webb County, TX (Zone 9b) Year-round
303 days
Last Spring Frost February 9
303 growing days
First Fall Frost December 9
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Webb County Soil Profile

Soil Type

Loam

Soil pH

6.6-7.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (198 days to spare)
Transplant: Jan 19 🍅 Harvest: Mar 23 – May 18
Recommended (50%) ✓ Fits season (184 days to spare)
Transplant: Feb 9 🍅 Harvest: Apr 13 – Jun 8
Safe Start (90%) ✓ Fits season (172 days to spare)
Transplant: Mar 5 🍅 Harvest: May 7 – Jul 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 Webb County

How your county's soil matches Corn's growing requirements.

Soil pH

Your soil pH (6.6–7.7) is more alkaline than Corn prefers (6.0–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

The loam soil in Webb County is excellent for Corn — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.3%). Annual compost additions will help Corn.

How to Plant Corn

1"
Planting Depth
12"
Between Plants
36"
Between Rows

Succession Planting Corn

6
successive plantings in your 303-day season

Sow every 6.9 weeks. Last sowing by Aug 31 to harvest before frost.

Plant Water Budget

Plant needs
1.5″/week
Rainfall provides
0.7″/week
You supply
1.0″/week
Watering frequency 2-3 times/week
Season total 2,587 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Corn

Corn 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 Corn Needs Rainfall You Supplement Action
Jan 1.3" 0" ❄️ Dormant
Feb 6.5" 1.9" 4.6" 🚿 Regular watering
Mar 6.5" 2.8" 3.7" 🚿 Regular watering
Apr 6.5" 5" 1.5" 💧 Light watering
May 6.5" 8.3" 0" ✅ Rainfall sufficient
Jun 6.5" 7.6" 0" ✅ Rainfall sufficient
Jul 6.5" 5.9" 0.6" 💧 Light watering
Aug 6.5" 6.4" 0.1" 💧 Light watering
Sep 6.5" 5.2" 1.3" 💧 Light watering
Oct 6.5" 3.4" 3.1" 💧 Light watering
Nov 6.5" 1.7" 4.8" 🚿 Regular watering
Dec 6.5" 1.5" 5" 🚿 Regular watering

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

Corn 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.

Corn needs ~1,700 GDD — county provides 6,460 GDD Excellent fit

Corn Planting Timeline — Webb County, TX

Corn Planting Calendar

Activity When Date Range
Direct Sow February 16 Feb 16 – Mar 9
Harvest April 20 Apr 20 – Jun 15

Plant 1" deep · 12" apart · Rows 36" apart

Month-by-Month Timeline

MonthActivities
January
February Direct Sow
March Direct Sow
April Harvest
May Harvest
June Harvest
July
August
September
October
November
December
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Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1.5"/week · 2-3 times/week

📅 Days to Maturity

60–100 days

🧪 Soil pH

Needs 6–7 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 9b

📆 Growing Season

303 days in Webb County

Growing Tips for Corn in Webb County

Direct sow Corn outdoors after February 09 in Webb County when soil has warmed and frost danger has passed.

Common pests for Corn in this region include corn earworm and corn borers. Use row covers early in the season and inspect plants weekly.

General growing tips

Plant in blocks of at least 4 rows rather than single rows for proper pollination. Direct sow after soil reaches 60F. Side-dress with nitrogen when plants are knee-high.

Recommended Corn Varieties for Webb County

Heat-tolerant varieties that silk well in high temps

Silver Queen (92d) Incredible (85d)

Companion Planting

Good Companions

Avoid Planting Near

  • Tomatoes
  • Celery

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Corn in Webb County, TX?

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

What planting zone is Webb County, TX?

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

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Your Webb County Garden Planner — Free

A 24-page printable planner built for Webb 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 Webb 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.