Welsh Onion illustration

Growing Welsh Onion in Zone 3b

Zone 3b has harsh winters and a short growing season. Start Welsh Onion early indoors to maximize your harvest window. Last frost: May 15. First frost: Sep 22.

Planting Calendar

Indoor
Outdoor
Harvest
Mar 6Sep 22

Season: May 15 – Sep 22 (130 days)

Zone3b
Last FrostMay 15
First FrostSep 22
Season Length130 days
Days to Harvest60
SunFull Sun
Frost ToleranceModerate
Spacing6/sqft

When to Plant Welsh Onion in Zone 3b

Start Seeds Indoors: Mar 6

Start Welsh Onion seeds indoors around Mar 6 (10 weeks before last frost). Optimal germination temperature: 70°F. Germinates in 7–14 days.

Transplant Outdoors: Apr 17

Transplant Welsh Onion seedlings outdoors after Apr 17. Wait until soil temperature reaches 45°F. Space plants at 6/sqft. Harden off plants for a week before moving outside.

Harvest: Jul 6

First harvest approximately Jul 6 (~80 days from transplant). Continue harvesting until first frost (Sep 22).

Frequently Asked Questions

When should I plant Welsh Onion in Zone 3b?

Start Welsh Onion seeds indoors around Mar 6. Transplant outdoors after Apr 17. Expect first harvest around Jul 6.

What is the last frost date for Zone 3b?

The average last spring frost date for Zone 3b is May 15. The first fall frost averages Sep 22, giving a 130-day growing season.

Can I grow Welsh Onion in Zone 3b?

Yes. Welsh Onion needs 60 days to harvest. Zone 3b has a 130-day growing season, which is sufficient.

What is the best month to plant Welsh Onion in Zone 3b?

The best time to start Welsh Onion in Zone 3b is Mar. Begin seeds indoors around Mar 6, then transplant outdoors after the last frost date of May 15.

How long does Welsh Onion take to harvest?

Welsh Onion takes approximately 60 days from planting to harvest. In Zone 3b, expect your first harvest around Jul 6.

Plan Your Welsh Onion Garden

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

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