Growing onions in zone 6
Bulbing is triggered by day length: long-day varieties for the North, short-day for the South, intermediate in between — the wrong type simply won’t bulb. Sets are easiest; transplants give bigger bulbs.
Zone 6 covers mid-Atlantic, Ohio Valley, Kansas, inland Pacific Northwest — nearly 200 frost-free days — almost everything grows, and fall gardens are easy. Zone dates are medians: frost timing varies within a zone with elevation and terrain, so treat these windows as a solid default and refine them with your own city’s dates below.
Make it local
These windows use zone 6's typical frost dates (last frost ~Apr 10, first frost ~Oct 22). For windows computed from your frost dates, run the ZIP code frost lookup and open the planting calendar — it remembers your city. The seed starting scheduler turns the whole seed rack into one printable, date-sorted list.
Frequently asked questions
When do I plant onions in zone 6?
Transplant Feb 27 – Mar 13, counted from zone 6's typical last frost around Apr 10. As a hardy crop it tolerates the light frosts on either side of that window.
When should I start seeds indoors for onions in zone 6?
Sow indoors Jan 30 – Feb 13 — that's 10 to 8 weeks before the typical Apr 10 last frost, giving sturdy transplants exactly when the garden is ready for them.
Can I direct sow onions in zone 6?
Yes — direct sow Mar 13 – Mar 27. Transplants buy a head start, but direct-sown plants catch up quickly once soil warms.