How to Grow Onion

Ready to grow Onion?

Order seeds from trusted suppliers.

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🛠️ Supplies You'll Need

🌱 Seed Starting Trays 🪴 Seed Starting Mix 💡 Grow Lights 🌡️ Heat Mat 🪵 Raised Garden Bed 🌍 Vegetable Garden Soil 🛠️ Hand Trowel Set 🚿 Watering Can

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Find Your Onion Planting Dates

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🌿 Plant Overview

Scientific Name Allium cepa

Category vegetable

Type Bulb

Days to Maturity 100 days

Starting Method Start Indoors

☀️ Growing Requirements

☀️

Sun

Full Sun (6+ hours)

💧

Water

Moderate

↔️

Spacing

4" apart

🌱

Depth

0.5" deep

📏

Height

12-18"

🌱

Germination

7-10 days

Ready to Grow Onion?

Find quality seeds from trusted suppliers.

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🤝 Good Companions

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⚠️ Avoid Planting Near

BeanPeaAsparagus

Onion Planting Calendar by Zone

Onion Planting Calendar by State

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Frequently Asked Questions

When should I plant Onion? +

Start Onion seeds indoors 8 weeks before your last frost date, then transplant outdoors 2 weeks after the last frost. Use the search on this page to find exact dates for your ZIP code or city.

How long does Onion take to grow? +

Onion typically matures in about 100 days from planting. Exact timing varies by variety, soil conditions, and local climate.

Should I start Onion indoors or direct sow? +

Onion should be started indoors 8 weeks before the last frost date. This gives seedlings time to establish before being transplanted outside after frost danger has passed.

How much sun does Onion need? +

Onion requires full sun (6+ hours) to thrive.

How far apart should I plant Onion? +

Space Onion plants 4 inches apart to allow adequate airflow and root development.

How much water does Onion need? +

Onion has moderate water needs. Consistent moisture is important especially during germination and early growth.

About Onion

Essential kitchen staple. Choose short-day or long-day varieties based on your latitude.

Expect your Onion to be ready for harvest in approximately 100 days from planting.

Use the search above or browse by zone or state to find the perfect planting dates for your location.