Growing bok choy in zone 4
Bok choy bolts at the first sign of stress in spring, so fall sowings are usually more reliable. Harvest whole heads or pull outer stalks; baby bok choy is ready in a month.
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 bok choy in zone 4?
Direct sow Apr 14 – Apr 28, 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.
Can I direct sow bok choy in zone 4?
Yes — direct sow Apr 14 – Apr 28. This crop prefers direct sowing; its roots dislike transplanting.
Can I plant bok choy for a fall harvest in zone 4?
Yes — sow Aug 6 – Aug 20, counted back from the typical Oct 1 first frost so plants mature before serious cold. Light fall frosts improve flavor rather than ending the crop.