Flowers

How to Plant Ornamental Kale: Timing, Spacing, Care & Color

Quick answer

Sow indoors about 12 weeks before the first fall frost (WI). Fall bedding plant — not a spring heat crop. Distinct from edible kale.

Ornamental kale at a glance

PlantStart indoors: 12 wk before last frost
SunFull sun for best color; cool nights drive pigment (WI/UC).
SpacingGrow on as container transplants; set out for fall color displays at nursery spacing for the cultivar size.
Days to harvestFall color when nights cool (WI/UC)
-13-12-11-10-9-8-7-6-5-4-3-2-1LF+1+2+3
■ Start indoors   ■ Plant out   ■ Harvest
Weeks relative to last frost (LF). Colored weeks show when our ZIP planner schedules each step.
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Updated

Safety: UC ANR notes “Roots of the plant are poisonous.” Grown as ornamental bedding.

Ornamental kale
Ornamental kale (Brassica oleracea). Photo: Oleg Yunakov, Wikimedia Commons, CC BY-SA 4.0 (resized).

Sourced from university extension guides. For dates where you live, use the ZIP planting planner.

Planting timing

Wisconsin Horticulture: do not rely on spring set-out (bolts/declines in heat). “Sow seed indoors about 12 weeks before the first fall frost.” Germinate about 70–75°F; grow seedlings cooler 60–65°F. Color intensifies with frost/cold; vivid below 50°F; acclimated plants to about 5°F. (WI ornamental cabbage and kale) NC: plant transplants as weather cools in fall; cold tolerant to 5°F. (NC ornamental kale) UC: plant seed about 75 days before cool nights; ≥2 months in containers before landscape transplant. (UC ornamental cabbage/kale)

Depth and spacing

Grow on as container transplants; set out for fall color displays at nursery spacing for the cultivar size.

Sun, soil and water

Full sun for best color; cool nights drive pigment (WI/UC).

Care

Keep seedlings cool to prevent bolting (NC/WI). Spring plantings decline in heat.

Display and lifespan

Grown for foliage color, not flowers (WI). Color full about 3–4 weeks after cool nights begin (UC).

Pests and diseases

Cole-crop pests can apply; cultural monitoring first.

Related: ZIP planner · planting guides · all grow guides

Frequently asked questions

When do I start indoors?

About 12 weeks before first fall frost (WI).

Spring OK?

WI: spring set-out bolts/declines in heat — prefer fall.

Same as kale for eating?

No — ornamental types; see how to grow kale separate from this ornamental page.

Sources