Horticultural Planning Records Est. data · NOAA 1991–2020 · USDA 2023

Vegetable · Brassicaceae

How to Grow Sea Kale

Cool season Frost hardy Full sun
Days to maturity 365–540
Spacing 24"
Plants / sq ft 0.2
Season Cool

Planting Sea Kale

Sea Kale is a cool season vegetable in the Brassicaceae family. Getting the timing right is the difference between a strong stand and a disappointing one, so the windows below are given relative to your own last spring frost and first fall frost rather than a generic calendar date. Look up your local frost dates and count back or forward from there.

You can sow Sea Kale directly into the garden 0–2 weeks before your last frost.

Sea Kale can be grown by transplanting and direct sowing. Direct sowing avoids transplant shock, while direct sowing is simplest where the season is long enough.

Spacing and Planting Depth

Give Sea Kale room to mature. The figures below come from verified extension and seed-supplier data for typical varieties.

Spacing in row24 inches
Row spacing30 inches
Plants per sq ft0.2
Planting depth0.5 inches
Sun requirementFull sun

Days to Maturity

Sea Kale reaches maturity in 365–540 days from sowing.

Sea Kale is ready to harvest after about 453 days. Harvest before summer heat or, for fall crops, before a hard freeze, to keep quality high.

Conditions and Care

As a cool-season vegetable, Sea Kale does its best growing in the cooler weather of spring and fall and tends to bolt or turn bitter in summer heat. It is frost hardy and can shrug off light freezes, so it can stay in the ground later into the season than tender crops.

Sea Kale needs full sun — give it at least six hours of direct light a day for the best growth and flavor. Sow seed about 0.5 inches deep, then keep the soil evenly moist until seedlings establish.

Sea Kale belongs to the Brassicaceae family; rotating where you grow members of this family each year helps limit the build-up of soil-borne pests and disease. Sea Kale is generally grown as a single planting each season rather than succession sown.

Growing Notes

Perennial; blanched spring shoots are the crop. First harvest year 2.

Plan your Sea Kale schedule

Sea Kale is typically grown as a single planting per season rather than succession sown. Plan your full garden →

Data sources
  • Cornell Extension