Growing kale in zone 4
Spring kale is good; fall kale is better — light frosts convert starches to sugars. Harvest outer leaves and the plant keeps producing for months. In zones 7+, kale often stands all winter.
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 kale in zone 4?
Transplant Apr 7 – Apr 21, 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 kale 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 kale in zone 4?
Yes — direct sow Apr 7 – Apr 21. Transplants buy a head start, but direct-sown plants catch up quickly once soil warms.
Can I plant kale for a fall harvest in zone 4?
Yes — sow Jul 9 – Jul 23, 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.