Flowering Kale: The Coolest Cool-Season Ornamental

The distinctive rosette of ornamental kale

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 and rosette but is also one of just a few species that thrives in cold weather. Indeed, flowering kale likes cold temperature so much 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?

Things can get confusing at the nursery. Even though they belong to the same family, cabbage and kale are actually not the same. Cabbage is a multi-layered vegetable whose leaves come together to form a head.

Cabbage head growing in the garden

Conversely, kale has a cluster of upright, open leaves called a rosette.

Ornamental kale

That being said, you will generally find ornamental varieties with broad, flat leaves labeled as ‘cabbage’ and those with ruffled, crinkled or curled leaves labeled as ‘kale’ at the store. 

BORN TO BE BEAUTIFUL

Selectively bred to produce spectacular leaves and rosettes, flowering kale comes in all shapes and sizes. The outer leaves are typically blue-green in tone while the rosettes start out pale green, then gradually shift to pink, red, purple, or cream depending on variety. The florets expand as temperatures cool, .

The distinctive, blue-green outer leaves of flowering kale

In recent years, innovations in color and form have made ornamental kale a ‘must-have’ in fall gardens. The new hues work beautifully with chrysanthemums, pot marigolds and pansies. And the variety in sizes makes the plant perfectly suited to just about every container.

Flowering kale rosette featuring ruffled edges

Best of all, flowering kale usually reaches its crescendo just after the first frost. And some plants maintain their intensity 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 throw it out after the first year.

FLOWERING KALE CARE

Ornamental kale and cabbage require very little maintenance and are bothered by few pests. They prefer moist, well-drained soil and benefit from feeding. For the best color, position your plants in full sun.

Since there won’t be much top growth after September, look for ornamental kale in one gallon size pots. Then keep spacing tight (10 to 12 inches) to encourage the rosettes to remain small. Over time, plants generally attain a width of approximately 12 inches.

THE MOST POPULAR VARIETIES

Ready to get started? 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. Use it by itself in a parterre garden, or try massing it behind annuals like chrysanthemums, pansies and violas in contrasting colors.

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.

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 resembles cabbage with its 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 change color. I’ll often combine different colors to form geometric patterns.

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.

Osaka series ornamental kale has flat green leaves like cabbage

IDEAS FOR DESIGNING WITH FLOWERING KALE

Due to its wide range of sizes, flowering kale looks equally good mixed with other flowers or all on its own in a single container. Below is a parterre garden I created using two broad-leaved varieties. 

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

The tall, frilly purple and green varieties and the broadleaf Osaka make a contrasting statement in large containers. In this planter box, the trailing ends of bright green lysimachia soften the mix.

The Impatient Gardener/Pinterest

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

Fall container with ornamental kale/herebydesign

In this formal urn, I played up the drama using tall grasses as a centerpiece. Then I added different varieties of red and green flowering kale, purple violas and mahogany-toned potato vine to create a warm-toned composition. 

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

Since ornamental kale retains its color well into winter, it also pairs beautifully with evergreen branches, pinecones and catkins to form stunning holiday arrangements.

Photo Credit/Canadian Gardening Magazine

In the garden, deep purple varieties like Redbor pair beautifully with salmon chrysanthemums and straw-colored grasses. The maiden grasses’s creamy plumes add a delicate touch.

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 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 help pump up the volume.