Growing Green Onion in Zone 10a

Zone 10a has a year-round growing season. Green Onion can be planted almost any time with proper planning. Last frost: Feb 20. First frost: Dec 1.

Planting Calendar

Indoor

Outdoor

Harvest

Jan 9Dec 1

Season: Feb 20 – Dec 1 (284 days) · Succession: plant every 3 weeks (up to 10x)

Zone10a

Last FrostFeb 20

First FrostDec 1

Season Length284 days

Days to Harvest65

Sunfull-to-part

Frost ToleranceHeavy

Spacing16/sqft (3" apart)

When to Plant Green Onion in Zone 10a

Start Seeds Indoors: Jan 9

Start Green Onion seeds indoors around Jan 9 (6 weeks before last frost). Optimal germination temperature: 65°F. Germinates in 7–14 days.

Transplant Outdoors: Feb 6

Transplant Green Onion seedlings outdoors after Feb 6. Wait until soil temperature reaches 40°F. Space plants at 16/sqft (3" apart). Harden off plants for a week before moving outside.

Harvest: Mar 18

First harvest approximately Mar 18 (~40 days from transplant). Continue harvesting until first frost (Dec 1). Green Onion can overwinter in mild climates for continued harvest.

Fall Planting: Oct 6

For a fall harvest, plant Green Onion around Oct 6 (8 weeks before first frost).

Companion Planting

✅ Carrot ✅ Beet ✅ Lettuce ✅ Tomato✅ Pepper✅ Cabbage✅ Strawberries

❌ Bean❌ Pea

Green Onion in Other Zones

1a 1b 2a 2b 3a 3b 4a 4b 5a 5b 6a 6b 7a 7b 8a 8b 9a 9b 10a 10b 11a 11b 12a 12b 13a 13b

Frequently Asked Questions

When should I plant Green Onion in Zone 10a?

Start Green Onion seeds indoors around Jan 9. Transplant outdoors after Feb 6. Expect first harvest around Mar 18.

What is the last frost date for Zone 10a?

The average last spring frost date for Zone 10a is Feb 20. The first fall frost averages Dec 1, giving a 284-day growing season.

Can I grow Green Onion in Zone 10a?

Yes. Green Onion needs 65 days to harvest. Zone 10a has a 284-day growing season, which is sufficient. You can plant up to 10 successions.

What is the best month to plant Green Onion in Zone 10a?

The best time to start Green Onion in Zone 10a is Jan. Begin seeds indoors around Jan 9, then transplant outdoors after the last frost date of Feb 20.

What companion plants grow well with Green Onion?

Good companion plants for Green Onion include Carrot, Beet, Lettuce, Tomato, Pepper, Cabbage. Avoid planting Green Onion near Bean, Pea.

How long does Green Onion take to harvest?

Green Onion takes approximately 65 days from planting to harvest. In Zone 10a, expect your first harvest around Mar 18.

Plan Your Green Onion Garden

Track Green Onion from seed to harvest with personalized frost dates, watering recommendations, and companion planting visualization.

Start Free Green Onion Growing Guide