Growing brussels sprouts in zone 4
Brussels sprouts are a marathon: transplant around last frost and harvest after fall frosts sweeten the sprouts. Pick from the bottom up, and top the plant in late summer to size up the whole stalk.
Zone 4 covers northern Plains, northern New England, much of Montana and Wyoming — about 150 frost-free days — most vegetables work, long-season melons are a stretch. 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 4's typical frost dates (last frost ~May 5, first frost ~Oct 1). 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 brussels sprouts in zone 4?
Transplant May 5 – May 19, counted from zone 4's typical last frost around May 5. As a hardy crop it tolerates the light frosts on either side of that window.
When should I start seeds indoors for brussels sprouts in zone 4?
Sow indoors Mar 24 – Apr 7 — that's 6 to 4 weeks before the typical May 5 last frost, giving sturdy transplants exactly when the garden is ready for them.
Can I direct sow brussels sprouts in zone 4?
Not usefully in zone 4 — brussels sprouts needs more growing time than direct sowing allows, which is why it's raised from transplants started indoors Mar 24 – Apr 7.