🍉 Can I Plant Watermelon in Des Moines, IA?

2026 planting guide for Zone 5b · Last frost ~April 28 · Growing season ~169 days

⏳ WAIT — Too cold — lows near 51°F (min 60°F)

Watermelon needs nights consistently above 60°F to thrive. Current forecast lows of ~51°F are below that threshold. Wait for warmer overnight temperatures.

Planting window: Jun 29 – Jul 13
Wait until overnight lows are consistently above 60°F before planting.
Live result based on current forecast for Des Moines, IA · Updates every 6 hours
USDA Zone
5b
Last Spring Frost
~April 28
First Fall Frost
October 14
Growing Season
~169 days
Ideal Temp for Watermelon
70–95°F
Frost Risk
⚠️ Sensitive

Growing Watermelon in Des Moines

Des Moines's Zone 5b Great Plains climate offers about 168 frost-free days. Iowa's legendary agricultural soils — some of the richest in the world — make home vegetable gardening naturally productive. Warm-season crops need indoor starts in late March, with transplanting in late April or early May. The warm, sunny Midwestern summers accelerate growth once established, and the rich loam soils support impressive vegetable yields.

In Des Moines (last frost around April 28), aim to direct sow or transplant watermelon outside around May — approximately 2 weeks after your last expected frost. Starting seeds indoors 4 weeks before the last frost date gives you a significant head start.

Watermelon thrives between 70°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 70–90 days from transplant to first harvest. Needs very warm conditions.

Frequently Asked Questions

When can I plant watermelon in Des Moines, IA?

In Des Moines (last frost around April 28), aim to direct sow or transplant watermelon outside around May — approximately 2 weeks after your last expected frost. For best results, start seeds indoors 4 weeks before that — giving you strong transplants ready to go out at the right time.

What is the USDA hardiness zone for Des Moines?

Des Moines, IA is in USDA Plant Hardiness Zone 5b. The last expected spring frost is around April 28, and the first fall frost arrives around October 14. This zone classification helps you understand which perennials survive winter and when annual vegetables can safely go outdoors.

Is it safe to plant watermelon outside in Des Moines right now?

That depends on the current weather forecast. Watermelon needs temperatures above 60°F (ideally 70–95°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 watermelon in Des Moines 2026?

Yes — Watermelon grows well in Des Moines, IA. With a Zone 5b climate and a growing season of ~169 days, Des Moines is well-suited for warm-season crops like watermelon. Just wait until after the last frost (around April 28) before moving plants outside.

Grow Watermelon in Other Cities

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 watermelon right now.

Check My ZIP Code →