Blog

When to Plant Sweet Corn in USDA Zone 5b

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.

In Zone 5b, the average last spring frost is around April 18 and the first fall frost is around October 13, giving you a growing season of approximately 178 days.

Zone 5b Moderate season
178 days
Last Spring Frost April 18
178 growing days
First Fall Frost October 13

Sweet Corn Planting Timeline — Zone 5b

Where Is USDA Zone 5b?

The map below highlights the states that contain Zone 5b. Click any state to see the Sweet Corn planting schedule for that location.

Prints a clean, ink-friendly version without maps or navigation.

Sweet Corn Planting Calendar — Zone 5b

Activity When Date Range
Direct Sow April 25 Apr 25 – May 16
Harvest June 27 Jun 27 – Aug 8

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

Free Zone 5b Planting Calendar PDF

Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 5b with start dates, transplant windows, and harvest times.

Get My Free Calendar →

Growing Conditions

Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

Days to Maturity

60–90 days

Soil pH

6 – 7

Zone Temperature Range

-15°F to -10°F average annual minimum

Growing Season

178 days (Zone 5b average)

Planting Specifications

Planting Depth1 inches
Plant Spacing12 inches apart
Row Spacing36 inches between rows

Succession Planting Sweet Corn in Zone 5b

3
successive plantings in Zone 5b's ~178-day season

Sow every 6.9 weeks for continuous harvest throughout the season.

Growing Tips for Sweet Corn in Zone 5b

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

Level Up Your Garden

Saving Sweet Corn Seeds

Recommended for Your Garden

🌱
Seed Starting Trays $8-20

Start seeds indoors with reusable cell trays and humidity domes.

🧪
Soil Test Kit $12-25

Test your soil pH, nitrogen, phosphorus, and potassium levels before planting.

🏷️
Garden Plant Markers $6-12

Keep your garden organized with durable, weather-resistant plant labels.

Related Plants

Frequently Asked Questions

When should I plant Sweet Corn in Zone 5b?

In Zone 5b, plan your Sweet Corn planting around the average last frost date of April 18. Direct sow outdoors around April 25.

Can Sweet Corn grow in Zone 5b?

Yes, Sweet Corn can grow well in Zone 5b, hardy in USDA zones 3a through 11b. Zone 5b has a growing season of approximately 178 days, which is sufficient for Sweet Corn (60-90 days to maturity).

When can I harvest Sweet Corn in Zone 5b?

In Zone 5b, expect to harvest Sweet Corn from June 27 – August 8. Sweet Corn takes 60-90 days from planting to harvest.

What is the last frost date for Zone 5b?

The average last spring frost in Zone 5b is around April 18, and the first fall frost is around October 13. This gives a growing season of approximately 178 days. These are 50% probability dates — actual frost dates vary year to year.

What should I plant next to Sweet Corn?

Good companion plants for Sweet Corn include Squash Summer, Green Beans, Cucumber. These companions can help with pest control, pollination, and nutrient sharing.

🌱

Plan Your Garden with Confidence

Get our free Garden Planner — organize your planting dates for Zone 5b, track your crops, and plan your garden season from seed to harvest.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals, University Cooperative Extension planting guides. Planting dates are estimates based on average frost dates — local conditions may vary. Last updated: April 2026.