Safe to Plant

Vegetable · Brassicaceae

When to plant kai-lan

Grown for the thick flowering stem rather than a head, and cut just as the first buds show. Faster than broccoli and far less fussy about heat.

Sow direct

2 weeks after

Counted from your last spring frost.

Days to maturity

50-70

From sowing to a first picking.

Frost tolerance

Half hardy

How much cold the plant itself will take.

Those weeks become real dates once you name a place.

Timing, in frost-relative terms

Seed packets rarely give calendar dates, because a date that suits one latitude is wrong at another. They give offsets from the last spring frost instead, and those offsets are what make kai-lan plantable anywhere.

  • Sow direct 2 weeks after the last frost.
  • Expect 50–70 days to maturity, counted from sowing.
  • Sow again every 21 days for a continuous supply.

Getting the timing right

Sow from two weeks after the last frost and again every three weeks. Cutting the main stem above a leaf brings a second flush of side shoots.

Frost tolerance

Takes a light frost around -4C. Cold makes the stems sweeter but slows them to a stop, so late sowings need a cloche to finish.

Classified as half-hardy, with damage expected below -4°C (24.8°F).