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When to Plant Sweet Corn in Oldham County, TX

Oldham County, Texas Zone 7a May

Your May gardening checklist

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

Avg. last frost April 19
Avg. first frost October 18
Soil temp (4") 64°F
Watering High
Pest pressure Moderate
Daylight 13.9 hrs
Before June arrives, get these ready
  • First harvests: sweet corn

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Sweet corn is bred for high sugar content in its kernels, which convert to starch rapidly after harvest. Modern supersweet varieties hold their sweetness longer.

Oldham County, Texas is in USDA Zone 7a. The average last spring frost is April 19 and the first fall frost is October 18, giving you a growing season of approximately 182 days.

At an elevation of 2,350 feet, Oldham County receives approximately 56 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 94°F, providing good warmth for Sweet Corn during the growing season. Sandy soil warms quickly in spring — great for early planting — but Sweet Corn will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Sweet Corn root diseases.

Oldham County, TX (Zone 7a) Moderate season
182 days
Last Spring Frost April 19
182 growing days
First Fall Frost October 18

Oldham County Soil Profile

Soil Type

Sandy Loam

Soil pH

7.2-8.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (77 days to spare)
Transplant: Apr 14 🍅 Harvest: Jun 16 – Jul 28
Recommended (50%) ✓ Fits season (77 days to spare)
Transplant: Apr 19 🍅 Harvest: Jun 21 – Aug 2
Safe Start (90%) ✓ Fits season (81 days to spare)
Transplant: May 3 🍅 Harvest: Jul 5 – Aug 16

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 Oldham County

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

Soil pH

Your soil pH (7.2–8.3) is more alkaline than Sweet Corn prefers (6.0–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

Sandy soil in Oldham County warms quickly in spring but drains fast. Sweet Corn will need more frequent watering and regular compost additions to retain nutrients.

Organic Matter

Organic matter is low (0.9%). Add 2-3 inches of compost before planting Sweet Corn.

How to Plant Sweet Corn

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

Succession Planting Sweet Corn

3
successive plantings in your 182-day season

Sow every 6.9 weeks. Last sowing by Jul 20 to harvest before frost.

Plant Water Budget

Plant needs
1.5″/week
Rainfall provides
1.3″/week
You supply
0.3″/week
Watering frequency Only during dry spells
Season total 404 gal / 100 sq ft
Drought risk

Water stress score is 8/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Sweet Corn

Sweet 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 Sweet Corn Needs Rainfall You Supplement Action
Jan 3.4" 0" ❄️ Dormant
Feb 3.4" 0" ❄️ Dormant
Mar 3.1" 0" ❄️ Dormant
Apr 6.5" 1.8" 4.7" 🚿 Regular watering
May 6.5" 1.3" 5.2" 🚿 Regular watering
Jun 6.5" 1.9" 4.6" 🚿 Regular watering
Jul 6.5" 10.4" 0" ✅ Rainfall sufficient
Aug 6.5" 12.7" 0" ✅ Rainfall sufficient
Sep 6.5" 6.7" 0" ✅ Rainfall sufficient
Oct 6.5" 4.7" 1.8" 💧 Light watering
Nov 3.1" 0" ❄️ Dormant
Dec 3.6" 0" ❄️ Dormant

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

Sweet 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.

Sweet Corn needs ~1,538 GDD — county provides 3,731 GDD Excellent fit

Sweet Corn Planting Timeline — Oldham County, TX

Sweet Corn Planting Calendar

Activity When Date Range
Direct Sow April 26 Apr 26 – May 17
Harvest June 28 Jun 28 – Aug 9

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1.5"/week · Only during dry spells

📅 Days to Maturity

60–90 days

🧪 Soil pH

Needs 6–7 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 7a

📆 Growing Season

182 days in Oldham County

Growing Tips for Sweet Corn in Oldham County

Direct sow Sweet Corn outdoors after April 19 in Oldham County when soil has warmed and frost danger has passed.

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

Common pests for Sweet 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 for wind pollination. Direct sow after soil is warm. Isolate supersweet varieties from other corn types to prevent cross-pollination.

Companion Planting

Good Companions

Avoid Planting Near

  • Tomatoes

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Sweet Corn in Oldham County, TX?

Oldham County is in Zone 7a with an average last frost of April 19. Plan your Sweet Corn planting based on this frost date — see the calendar above for exact timing.

What planting zone is Oldham County, TX?

Oldham County, Texas is in USDA Hardiness Zone 7a. The average last spring frost is April 19 and first fall frost is October 18.

🌱

Your Oldham County Garden Planner — Free

A 24-page printable planner built for Oldham County (Zone 7a). 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 Oldham 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.