How to Grow Ornamental Cabbage & Kale for Fall Color

When the summer annuals collapse and frost threatens, ornamental cabbage and kale step in to carry the garden through fall and winter with rosettes of pink, purple, cream, and magenta foliage. These are not vegetables grown for the table but for show, bred from the same species as edible brassicas to produce dramatic, color-saturated leaf rosettes that look like giant frilly roses. The real magic is that they get better as the weather gets colder: the dazzling center color only develops once nighttime temperatures drop. Here is how to grow ornamental cabbage and kale for reliable cool-season color in beds and containers.

Ornamental Cabbage vs. Ornamental Kale

Both are forms of Brassica oleracea, the same species as edible cabbage and kale, but selected purely for their colorful foliage. The names are used loosely, but the practical distinction is in the leaves. Ornamental cabbage has broad, smooth-edged leaves that form a tighter, more rounded head-like rosette. Ornamental kale has more deeply ruffled, fringed, or feathery leaf edges, giving a frillier, looser, more textured look. Within both you will find color centers in white and cream, rose and pink, and deep purple-magenta, framed by green or blue-green outer leaves.

They are technically edible but were bred for looks, so the flavor is bitter and tough; treat them as decoration, not dinner, though the leaves and flowers make a striking, food-safe garnish if grown without pesticides. A single plant forms a low rosette typically 10–15 inches across and stays under a foot tall, making them ideal for the front of beds, mass plantings, and containers.

The Cold-Color Trick: Why Timing Is Everything

The most important thing to understand about these plants is that the vivid central coloring is triggered by cold. In warm weather they remain mostly green and unremarkable. Once nighttime temperatures fall consistently below roughly 50°F, the centers flush with their full pink, purple, white, or rose color. This is why you should never expect summer drama from them and why timing the planting matters so much.

The goal is to have full-sized plants in the ground just as the weather turns cool. Set transplants out about 6–8 weeks before your average first fall frost. That gives them time to bulk up while it is still mild, so that when the cold arrives they are large enough to put on a real show. Plant too late and you get small, underdeveloped rosettes; plant too early and they stretch and stay green through the warm weeks. In mild-winter regions (zones 8 and warmer) they can hold their color for months, often all the way through winter into early spring.

How to Plant Ornamental Cabbage and Kale

Starting From Seed

To grow your own, start seed about 8–10 weeks before your target transplant date, which usually means sowing in mid-to-late summer for a fall display. Sow seed about a quarter-inch deep in cell trays of moist seed-starting mix at around 65–75°F; germination takes 5–10 days. Because midsummer is hot, many gardeners start seed in a cooler, shaded spot or indoors with good light. Grow the seedlings on until they have several true leaves and a sturdy little rosette before setting them out.

Buying Transplants

Most gardeners simply buy potted transplants from a garden center in early fall, when they appear right on schedule for planting. Choose stocky, healthy plants and don’t worry if the color is still muted in the pot; it will intensify as nights cool. Avoid plants that are already stretched, yellowing, or showing aphid clusters in the leaf folds.

Spacing, Soil, and Planting Depth

Plant in full sun, at least six hours, for the best color and most compact form. They thrive in rich, fertile, well-drained soil with a pH around 6.0–7.5; work in compost before planting. Space plants 12–18 inches apart so each rosette has room to reach full size. One useful trick: because these brassicas grow on a stem that can lengthen, you can plant them slightly deeper than they sat in the pot, up to the lowest leaves, to keep the rosette sitting low and tidy. Water in well after planting.

Watering, Feeding, and Care

Keep the soil consistently moist, especially while plants are establishing and bulking up in the still-warm early weeks. Aim for about an inch of water per week, more in containers, which dry out faster. Water at the base to keep the dense foliage dry and reduce disease. A layer of mulch helps conserve moisture and moderate soil temperature.

Feed at planting with a balanced fertilizer or compost to support strong early growth, then ease off as cool weather arrives; you want sturdy, compact plants rather than soft, leggy growth. In containers, a single dose of slow-release fertilizer at planting is usually enough for the season. Remove any yellowing outer leaves to keep the display crisp. As cool-season plants, ornamental cabbage and kale actually sweeten in appearance after a frost; light freezes deepen and brighten the colors rather than harming the plants. They withstand hard frost and temperatures into the low 20s°F. Their decline comes in spring: as days lengthen and warm, the plants “bolt,” sending up a tall flower stalk and losing their tidy form, at which point they are best pulled and replaced.

Using Them in the Fall and Winter Garden

Ornamental cabbage and kale shine in mass plantings, where a sweep of rosettes reads like a living quilt of color, and they are unbeatable for refreshing tired fall containers and window boxes. Combine them with pansies, violas, mums, and ornamental grasses, or tuck them among spent summer annuals for an instant seasonal makeover. Their bold, geometric rosettes also pair beautifully with the fine texture of cool-season grasses and trailing ivy in a mixed pot. Because they hold up through cold that flattens most other flowers, they are a backbone plant for autumn and winter curb appeal. For more ways to keep beds and pots colorful as the seasons turn, explore our other flower and foliage growing guides, and consider pairing ornamental brassicas with cold-hardy bulbs for a long season of interest.

For containers specifically, think in layers: a tall “thriller” element such as an ornamental grass or a sturdy stem of dwarf conifer in the center, the bold rosettes of cabbage or kale as the “filler” around it, and a trailing element like creeping jenny or variegated ivy spilling over the rim. A single large ornamental kale can also stand alone as a striking specimen in a generous pot by a front door. Because the plants size up as the season cools, give them a slightly larger container than they appear to need at planting, and use a quality potting mix that drains freely so the crowded root zone never stays soggy.

Color combinations are worth planning, too. The cool pinks and purples of ornamental kale read beautifully against silver dusty miller, burgundy heuchera, and the soft blue of fall asters, while the white-and-green types lend a crisp, frosty look that pops against evergreens and dark mulch. In regions with mild winters, a planting set out in fall can carry its display straight through to early spring, making ornamental brassicas one of the longest-performing and most economical sources of cold-season color available.

Pests, Diseases, and Troubleshooting

Being true brassicas, ornamental cabbage and kale attract the same pests as their edible relatives, though cool fall weather reduces pressure compared to summer:

• Cabbage worms and loopers: green caterpillars that chew holes in leaves. Hand-pick, or use a Bt (Bacillus thuringiensis) spray.
• Aphids: they hide in the dense leaf folds; blast off with water or treat with insecticidal soap.
• Slugs and snails: rasp ragged holes, especially in damp weather; use bait or traps and clear debris.
• All-green, colorless centers: the weather hasn’t turned cold enough yet, or plants were set out too late. Color develops only once nights drop below about 50°F.
• Stretched, leggy plants: too much shade or warm-weather growth. Site in full sun and time planting to cool weather.
• Sudden flower stalk and loss of shape: spring bolting in response to warmth and longer days; pull and replace.