Flowering Kale: The Coolest Cool-Season Ornamental

Long before it became a trending food, flowering kale was a garden star, delivering a pop of color to fall’s graying landscape. The plant is not only prized for its striking foliage but it’s also one of just a few species that thrives in cold weather. In fact, flowering kale likes cold temperatures so much that it often stays attractive well into winter. I can’t think of a better choice for fall gardens and containers.

IS IT CABBAGE OR KALE?

People tend to confuse the name cabbage with kale. That said, even though both plants belong to the same species (Brassica oleracea), they exhibit distinctly different traits. Cabbage is a leafy green, red or white plant grown as a vegetable crop. Its tightly-packed leaves come together to form a head.

Cabbage head growing in the garden

Whereas flowering kale is grown primarily as an ornamental plant. Its green or purple, upright leaves fan outwards from a central part called a rosette.

The bright pink rosette of flowering kale.

Ornamental kale

Still, I’ve found that nurseries generally label kale varieties with broad, flat leaves as ‘ornamental cabbage’ and those with ruffled, crinkled or curled leaves as ‘ornamental kale’. Things can get confusing.

BORN TO BE BEAUTIFUL

Whatever its label, though, flowering (ornamental) kale is bred to produce spectacular leaves and rosettes. Moreover, it comes in all shapes and sizes. Most hybrids have blue-green outer leaves, while rosettes can vary from cream, pink, purple to red. The rosettes typically start out small and expand as temperatures cool, revealing ever more vivid color.

The distinctive, blue-green outer leaves of ornamental kale

And as a result of recent innovations in color, flowering kale is now also a good choice for fall/winter gardens (along with containers). All varieties combine beautifully with other cool-season plants like chrysanthemums, marigolds and pansies.  

Magenta-toned flowering kale with ruffled edges.

Flowering kale rosette featuring ruffled edges

But perhaps best of all, flowering kale reaches its crescendo just after the first frost. This is a time when most other plants have withered. Some varieties even retain their color all the way until spring.

flowering kale covered with snow

IS KALE A PERENNIAL?

Kale is a biennial, which means it has a two-year life cycle. The first year it produces leaves and the second year it produces flowers. Most people grow it for its ornamental qualities, however, and discard the plant after the first year. 

FLOWERING KALE CARE

Ornamental kale and cabbage require very little maintenance and are bothered by few pests. In addition to preferring moist, well-drained soil, they enjoy a little light feeding. For the best color, it helps to position them in full sun.

I look for plants in one-gallon size pots, then keep the spacing tight (10 to 12 inches) to encourage the rosettes to remain small. Over time, they usually attain a width of approximately 12 inches.

Small garden with geometric display of yellow and pink flowering kale.

POPULAR VARIETIES

Interested in learning more? Here are some of the most popular varieties:

REDBOR

Redbor has narrow, upright deep purple, ruffled leaves. It is the tallest kale grown and can reach a height of 3 feet. I’ve used it on its own to fill a parterre garden (the tall, frilly foliage contrasts beautifully with the clean-cut box). Or, try using it as a backdrop to annuals like chrysanthemums, pansies and violas in contrasting colors.

Redbor kale

Purple-leaved Redbor kale

PEACOCK SERIES

Peacock series ornamental kale are large, open and frilly plants that can reach 2 feet across. They feature deeply serrated, feather-like leaves and cream or red-toned centers. Extremely cold hardy, they can survive even the harshest of winters. White and silver look amazing with these varieties.

Peacock series ornamental kale

Deeply serrated, feather-like leaves distinguish Peacock kale

PIGEON SERIES

Pigeon Series (Pigeon Pink and Pigeon Red Pigeon Purple and Pigeon White) ornamental kale most closely resemble cabbage with their tight rosettes of light pink, dark red or creamy white. The round-shaped plants have wavy outer leaves that remain medium to dark green while the flower-like centers slowly change color. I often combine different varieties to form geometric patterns.

Pigeon series flowering kale

The tight rosettes of ornamental kale ‘Pigeon Series’

OSAKA

Osaka Pink, Osaka White and Osaka Red are often termed ornamental cabbage due to their smooth, flat leaves and tightly-packed rosettes. The plants produce layers of wavy edged green leaves while the florets gradually change to bright purple, pink or cream. These varieties are more structured in form and will stand on their own in a container.

Osaka series flowering kale

Osaka series ornamental kale has flat green leaves like cabbage

DESIGNING WITH FLOWERING KALE

Flowering kale’s wide range of colors and shapes can offer endless design possibilities. Below is a parterre garden I created using two broad-leaved varieties. We planted them tightly together to play up the geometrics.

Parterre garden with geometric arrangement of white and purple flowering kale.

Parterre with two different varieties of ornamental kale/herebydesign.net

In large containers, tall, frilly purple and green varieties like the broadleaf Osaka can create a strong contrast with other, smaller plants. Below, the trailing ends of bright green lysimachia add drama to the composition.

The Impatient Gardener/Pinterest

In this small container, I’ve combined ornamental ‘cabbage’ with violas and Swedish ivy. I chose the greenish-purple kale to complement the colors of the dusty red pot.

Fall container with pansies, Swedish ivy and flowering kale.

Fall container with ornamental kale/herebydesign

In this formal urn, I’ve used tall grass as the ‘thriller’. The ‘fillers’ and ‘spillers’ consist of different varieties of red and green flowering kale, purple violas and mahogany-toned potato vine. The effect is a lush, warm-toned composition.

Fall container with purple fountain grass, mahogany sweet potato vine and frilly green flowering kale.

Fall container with grasses, flowering kale and potato vine/herebydesign

Since ornamental kale retains its color well into winter, it can make a stunning addition to holiday arrangements.  Here, a green and white frilly variety pairs beautifully with evergreen branches, pinecones and catkins.

Photo Credit/Canadian Gardening Magazine

In this fall garden, the deep purple Redbor sets up a gorgeous color contrast with salmon chrysanthemums and straw-colored grasses. The maiden grasses’ creamy plumes add a nice textural touch to the composition.

Photo Credit/The Hoosier Gardener

Finally, when combining flowering kales with other plants, think about varying the foliage. Here, purple fountain grass and lime green potato vine provide color. And the frilly purple variety lends contrast. 

Photo Credit/Three Dogs In A Garden

Ready to get started? Check out your local nursery for the newest ornamental kale varieties. And don’t be afraid to combine them with other cool-season companions like evergreen branches, dried flower heads, catkins and berries. These fillers will add interest to your containers and keep the show going well into fall.