🌽 Can I Plant Corn in St. Louis, MO?

2026 planting guide for Zone 6b · Last frost ~April 5 · Growing season ~203 days

✅ YES — Conditions look good

Temperature conditions are suitable for Corn.

Planting window: Aug 13 – Aug 27
Good to go — plant now while conditions are right.
Live result based on current forecast for St. Louis, MO · Updates every 6 hours
USDA Zone
6b
Last Spring Frost
~April 5
First Fall Frost
October 25
Growing Season
~203 days
Ideal Temp for Corn
65–95°F
Frost Risk
⚠️ Sensitive

Growing Corn in St. Louis

St. Louis sits at the confluence of the Missouri and Mississippi rivers in Zone 6b, with about 202 frost-free days. The humid continental climate brings warm, productive summers ideal for tomatoes, peppers, cucumbers, and sweet corn. Spring arrives relatively early, and fall holds warmth well — excellent conditions for a September planting of cool-season greens that produce into November.

In St. Louis (last frost around April 5), aim to direct sow or transplant corn outside around April — approximately 2 weeks after your last expected frost.

Corn thrives between 65°F and 95°F. It is frost-sensitive, meaning a single freeze at 32°F will damage or kill it — always wait until frost danger has fully passed. Expect 60–100 days from transplant to first harvest. Needs warm soil. Plant in blocks.

Frequently Asked Questions

When can I plant corn in St. Louis, MO?

In St. Louis (last frost around April 5), aim to direct sow or transplant corn outside around April — approximately 2 weeks after your last expected frost.

What is the USDA hardiness zone for St. Louis?

St. Louis, MO is in USDA Plant Hardiness Zone 6b. The last expected spring frost is around April 5, and the first fall frost arrives around October 25. This zone classification helps you understand which perennials survive winter and when annual vegetables can safely go outdoors.

Is it safe to plant corn outside in St. Louis right now?

That depends on the current weather forecast. Corn needs temperatures above 55°F (ideally 65–95°F) to thrive. CanIPlant checks your real 7-day forecast and any active frost alerts to give you a live YES, NO, or WAIT answer — just enter your ZIP code.

Can I grow corn in St. Louis 2026?

Yes — Corn grows well in St. Louis, MO. With a Zone 6b climate and a growing season of ~203 days, St. Louis is well-suited for warm-season crops like corn. Just wait until after the last frost (around April 5) before moving plants outside.

Grow Corn in Other Cities

New York, NYLos Angeles, CAChicago, ILHouston, TXPhoenix, AZPhiladelphia, PASan Antonio, TXSan Diego, CA

Get a live answer for your exact address

Enter your ZIP code — CanIPlant checks your real 7-day forecast, frost alerts, and 30-year climate data to tell you whether to plant corn right now.

Check My ZIP Code →