🧅 Can I Plant Green Onion in Modesto, CA?

2026 planting guide for Zone 9b · Last frost ~February 5 · Growing season ~297 days

✅ YES — Good temps, but watch for heat — highs near 101°F

Temperature conditions are suitable for Green Onion. Highs near 101°F are on the warm side — make sure plants have plenty of water.

Planting window: Jul 9 – Jul 23
Good to go — plant now while conditions are right.
Live result based on current forecast for Modesto, CA · Updates every 6 hours
USDA Zone
9b
Last Spring Frost
~February 5
First Fall Frost
November 28
Growing Season
~297 days
Ideal Temp for Green Onion
50–80°F
Frost Risk
✅ Tolerant

Growing Green Onion in Modesto

Modesto's Zone 9b Central Valley location in Stanislaus County sits in the agricultural heartland of California. Hot, dry summers and mild winters support a long growing season. Tomatoes, peppers, corn, and melons thrive in Modesto's heat. Cool-season crops do well in fall and winter when temperatures moderate. The surrounding almond orchards signal how productive this region's sun and soil can be for diverse crops.

In Modesto (last frost around February 5), green onion can go out around January — approximately 4 weeks before the last expected frost, making it an early-season opportunity. Starting seeds indoors 8 weeks before the last frost date gives you a significant head start.

Green Onion thrives between 50°F and 80°F. It tolerates temperatures as low as 35°F, making it a candidate for early spring planting before the last frost date. Expect 60–80 days from transplant to first harvest. Easy and fast. Direct sow in early spring or fall. Harvest young.

Frequently Asked Questions

When can I plant green onion in Modesto, CA?

In Modesto (last frost around February 5), green onion can go out around January — approximately 4 weeks before the last expected frost, making it an early-season opportunity. For best results, start seeds indoors 8 weeks before that — giving you strong transplants ready to go out at the right time.

What is the USDA hardiness zone for Modesto?

Modesto, CA is in USDA Plant Hardiness Zone 9b. The last expected spring frost is around February 5, and the first fall frost arrives around November 28. This zone classification helps you understand which perennials survive winter and when annual vegetables can safely go outdoors.

Is it safe to plant green onion outside in Modesto right now?

That depends on the current weather forecast. Green Onion needs temperatures above 35°F (ideally 50–80°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 green onion in Modesto 2026?

Yes — Green Onion grows well in Modesto, CA. With a Zone 9b climate and a growing season of ~297 days, Modesto is well-suited for warm-season crops like green onion. As a frost-tolerant crop, green onion can even go out a few weeks before the last frost date.

Grow Green Onion in Other Cities

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