Zone 10 · Corn & Legumes Growing Guide

When to Plant Sweet Corn
in Zone 10

The three sisters classic. Needs to be grown in blocks (minimum 4×4) for wind pollination — a single row gives no ears. Sweetness drops fast after picking — eat within 30 minutes of harvest.

Plant outdoors
Feb 1 – Mar 15
Start indoors
Direct sow
Last Frost
~Jan 15
Days to harvest
65–90 days
Difficulty
Medium
Ready to harvest — Zone 10
Harvest window: Apr – Jun

Planting Calendar

In Zone 10, Sweet Corn should be planted outdoors Feb 1 – Mar 15, after the average last frost date of approximately Jan 15.

Spring crop mainly. Brief window before heat makes pollination unreliable.

Care Guide

Sunlight
Full sun · 6–8 hrs/day
Watering
High
Spacing
9–12 inches
Soil
Rich, well-draining, fertile
Days to maturity
65–90 days
Soil pH
6.0–6.8
plant tip · Zone 10

Spring crop mainly. Brief window before heat makes pollination unreliable.

Feeding Schedule

How often
twice a season
Feed type
high nitrogen
Key timing
at planting and when knee-high

Heavy feeder — apply nitrogen-rich fertilizer at planting and again when plants reach knee height. Tasseling onwards needs less nitrogen.

Succession Planting

Sow every 2 weeks

Sow every 2 weeks from last frost through early summer. Sweet corn is only good for a few days after harvest — succession means you're picking continuously rather than getting a huge harvest all at once that you can't eat fast enough.

Companion Planting for Sweet Corn

What you plant next to sweet corn makes a real difference — some plants actively help, others compete or attract pests.

Grows well with
  • Beans
  • Squash
  • Cucumbers
  • Sunflowers
Keep away from
  • Tomatoes
  • Brassicas
  • Fennel

These guides get better when growers like you contribute. If something’s wrong or you’ve learned something worth sharing, we’d love to hear it.

What needs correcting?

What should it say?

Your zone (optional)

Thanks — we'll review this and update the guide if needed.

Your growing tip for Sweet Corn

Your name (optional)

Your zone (optional)

Tips are reviewed before publishing. Accepted tips earn you a Founding Grower badge when the plant app launches.

Thanks for contributing! We'll review your tip and be in touch before launch.

Common questions

In Zone 10, direct sow sweet corn outdoors Feb 1 – Mar 15 after your last frost date of approximately Jan 15. Spring crop mainly. Brief window before heat makes pollination unreliable.
Zone 10 has an average last spring frost of approximately Jan 15 and a first fall frost around Dec 31. These dates vary by specific location — use your ZIP code in the plant app for precision based on the nearest NOAA weather station.
Good companion crops for sweet corn include Beans, Squash, Cucumbers, Sunflowers. Avoid planting near Tomatoes, Brassicas, Fennel, which can compete for nutrients or attract pests.
Sweet Corn typically takes 65–90 days from transplant or direct sow to harvest in Zone 10. Expected harvest window: Apr – Jun.

Free app · iOS February 2028

Track your Sweet Corn in plant

Get a live traffic light for every crop in your garden — zone-aware planting calendar, real-time weather alerts, and a community of growers near you.

Be first to back on Kickstarter and lock in the founding price.

Sweet Corn in other zones
Crop Guides