How to Grow and Care for Flowering Kale

Flowering kale looks very close to ornamental cabbage and their edible kale and cabbage relatives. Although they get lumped into the same species category as the edible ones, flowering kale have been specifically bred for looks over flavor. They are slightly bitter, and they’re popular for garnish. The leaves will form rosettes in rose, purple, and creamy white, and this makes them look like large flowers instead of vegetables.

In the horticultural trade, the varieties that produce smooth leaf margins with flat, broad leaves are usually referred to as flowering cabbages, and those that produce a fringed or serrated leaf edge are considered to be flowering kale. Technically, both are kales because kale leaves will form rosettes while a true cabbage forms a head.

Officially, flowering kale is a cool-season biennial. This means that your flowering kale will grow the vegetative leaves the first year and send flowers up the second year to produce seeds before the plant dies off. However, these fast-growing plants are usually grown as annuals purely for the foliage. They get planted from nursery starts in the early spring or late fall months and removed from the garden after they finish their seasonal display.

Flowering kale’s pretty purple, red, green, and white hues with the frilly or serrated foliage makes it an eye-catching plant to have in any garden.

Flowering Kale – General Information

Bloom Time:	Rarely flowers
Botanical Name:	Brassica oleracea var. sabellica
Common Name:	Flowering kale, ornamental kale
Family:	Brassicaceae
Flower Color:	N/A
Hardiness Zones:	2 to 11
Mature Size:	12 to 18 inches tall and wide
Native To:	Western and southern Europe
Plant Type:	Annual or biennial
Soil pH:	5.5 to 6.5 or slightly acidic
Soil Type:	Rich loam
Sun Exposure:	Full sun
Water Needs:	Medium with well-draining soil

Flowering Kale 101

Flowering kale falls into the Brassica oleracea var. Sabellica botanical name. It looks very close to the edible kale you see in salad bars, but they were created purely for looks instead of taste. The coloring of these plants usually includes pinks and purple with green mixed in, but there are a few cultivars that offer yellow and white in the center.

This plant offers wide, frilly leaves, and it’s a nice foliage plant to help fill in space in your garden. You’ll find that a lot of people mistakenly use the flowering cabbage and flowering kale names interchangeably, but they are different. You may even find them put into feather leaf or fringed leaf varieties in plant shops.

This plant adores cooler weather and it does best when the temperature dips below 60°F or has it as a high. The cooler the temperatures are, the more vibrant the coloring on this plant will be. In fact, it’ll keep the stunning colors until the temperatures fall below 20°F on a regular basis.

Types of Flowering Kale

Unless you have a commercial garden going, there isn’t a huge amount of variety to choose from when it comes to flowering kale. Most seed packets simply come labeled as “ornamental kale.” So, it’s best to go by color combination when you start looking at your plants. You can divide them into fringed leaf cultivars with ruffled leaves and feather leaf cultivars that have finely serrated leaves. A few popular varieties include:

• • ‘Chidori Ornamental Kale – This plant offers curly leaf edges, and the leaves are creamy white, purple, or a very deep magenta.

• ‘Color Up’ Kale – This kale has an upright growth habit with green leaves that surround a fuschia, pink, or white center.

• ‘Peacock’ Kale – This plant looks very close to the edible kale cultivars, and it has a loose growth habit combined with deeply serrated leaves in shades of white, purple, or red.

Where to Plant Flowering Kale

Ornamental kale is an excellent landscaping plant as well as a nice container plant. No matter if you plan on using it in a garden bed or in your container garden, it’s a nice complement to your other fall plants like ornamental peppers, chrysanthemums, and violas. Planting it in clusters of three will give you a very colorful, full look.

Another nice way to use flowering kale in your landscape or garden is to plant it in window boxes as a focal point alongside other seasonal plants like sedums or pansies. These plants usually won’t grow as quickly so you can plant them in tighter quarters.

If you live in a hotter climate, make sure you take steps to protect your kale in the hotter afternoon hours to prevent scorching it.

Flowering Kale Care

Flowering kale tends to be very easy to grow in sunny spots in your yard, but they can have problems with some of the pests that can plague other varieties in this family. They prefer to be in cooler weather, so you may be disappointed by the speed in which they bolt and go to seed if you grow them in a hot planting zone. The stunning colors they produce comes from planting them in cool or cold conditions.

Fertilizer

For steady growth, fertilize your flowering kale only when you plant them and make sure you use a balanced fertilizer. Don’t fertilize your plants as they grow or they can get leggy and lose the pretty coloring.

Light

These plants do best when you grow them under full sun conditions. However, when you grow them in warmer climates, afternoon shade is best so they don’t bolt quickly.

Soil

A loamy, organically rich soil that drains well will make your flowering kale thrive. They prefer to have a slightly more acidic pH level in the soil between 5.5 and 6.5.

Temperature and Humidity

Flowering kale won’t develop their full color potential until they get a good chill from a light frost. They can survive throughout the winter months, but how they look will heavily depend on the weather. If the weather is hot and the kale has long exposure to daylight, they will bolt or send up flowers before going to seed. If it’s very warm with harsher stormy weather, the plants will look tattered.

They can survive as long as the temperature stays 5°F and up. However, if you have temperatures plummet, this can damage or kill your flowering kale. Humidity usually isn’t too much of an issue for your plant. But, if the weather is damp and you don’t ensure good air circulation around them, they can run into problems with fungal diseases, and this usually occurs as leaf spots.

Water

Keep your plants watered well. They thrive in soil that is consistently moist but not soggy. If the top inch of soil dries out, it’s time to break out the hose and water them. If you get regular rain in your climate, you most likely won’t have to water much if at all. But, be prepared to supplement water during dry periods. Like a lot of plants, roughly an inch of water through irrigation or rainfall is perfect for them, but avoid over watering if you can.

Propagating Flowering Kale

This biennial plant is generally discarded before the second season rolls around when they flower and produce seeds. But, if you allow them to stay in the garden for the second season and set seeds, you can collect them as the flowers fade and replant them in the late fall or early spring months. You can also pop them into the freezer and preserve them to plant them later.

How to Grow Flowering Kale from Seed

To plant them in the spring, flowering kale seeds should start indoors roughly eight weeks before the last frost of the season. For a fall display, you’ll start your seeds roughly July 1st and plant the seedlings out in the garden in the middle of August. Start your seeds indoors in smaller pots filled with a seed starting potting soil mix. Plant your seeds rough ¼-inch deep and keep the soil moist. Set your seeds in a bright spot that is roughly 70°F. The seedlings will start popping through the soil and germinating in 10 to 21 days. You can replant the potted seedlings outside right away.

Flowering kale does very well in pots or planted in the ground in groups of three to create a very lush, full look.

Potting and Repotting Flowering Kale

If you’re only trying to get one or two plants, they tend to look much more natural when you grow them in containers instead of scattering them around the garden. They can make great seasonal potted plants, just like potted pansies look nice in the springtime and potted chrysanthemums look fabulous in the fall.

Pick a container that has ample drainage holes, and put an all-purpose potting mix into it. Nursery plants usually won’t get a lot bigger than they are when you first plant them, so you usually won’t have to worry about repotting them later in a bigger container.

Overwintering

Flowering kale is usually not allowed to overwinter because the second year they grow leaves them looking unattractive in your garden. Instead of the bold colors, you’ll get flower stalks that go to seed. But, most gardeners will leave them in the garden or pot well into the winter months since the rosettes will stay attractive until several hard frosts cause them to wilt.

Common Pests and Diseases

Like a lot of edible vegetables that fall into the Brassica genus, flowering kales tend to have issues with cabbage loopers, cabbage worms, caterpillars, flea beetles, slugs, thrips, and aphids. Hard sprays of water can help dislodge these pests from the leaves, and there are a variety of horticultural oils and pesticides that you can apply that are specially designed for vegetables that will work too. Any kale you plant in pots might be less prone to developing issues with pests or diseases when you compare them to ones planted in the garden.

Common Issues with Flowering Kale

Even though people use them ornamentally, flowering kale is essentially a vegetable, so it’s prone to developing issues that many of the common vegetables get. Some big issues you can run into include:

Black or Yellow Leaf Spots

Spots on the leaves instead of holes indicate that your flowering kale has a bacterial or fungal infection. These are much more likely to appear when the weather is damp. Ensuring there is good air circulation can help reduce the chances of this disease appearing, and fungicides may help to treat fungal disease if you catch them early enough.

Holes in Leaves

This is usually the work of one or more feeding insects that love to eat every member of the Brassicaceae family. Cabbage worms, a range of caterpillars, aphids, and slugs all view flowering kale and ornamental cabbages as a viable food source. There are several chemical spray and insecticidal soaps you can use to control the pests, and since you usually don’t eat this plant, you can be more liberal with the pesticides.

Tall Stalks Appear

If your otherwise attractive flowering kale plant suddenly sends up tall, sparse, and scraggly-looking stalks is in the process of bolting or going to flower. This means that it’s coming to the end of its life lifecycle as a pretty ornamental flower. You can keep it growing until the flowers fade and collect the seeds or you can pull the plant and start over the next spring.

Differences Between Flowering Kale and Cabbage

Flowering kale and cabbage are very similar in color, size, and looks. The biggest difference is that the cabbage leaves have very smooth edges and the kale leaves are crinkled and frilly.

These more showy vegetables are both cool-season biennials, but most people choose to grow them as annuals. Both are closely related to the edible cabbages and kales you can grow, and they’re hardy in zones 2 to 11. You can eat them too, but they have a very bitter taste because people bred them for looks. A few other differences include:

• Both look like big flowers in your landscape or garden
• Flowering cabbage will form a head with wide and flat leaves with smooth edges
• Flowering kale will form rosettes with serrated, frilly, or crinkled leaves along the edges.

Many people assume that flowering kale and flowering cabbage are the same thing, but they’re different plants.

Important Facts About Flowering Kale

For drama in your fall garden, it’s very hard to beat flowering kale. Sometimes people call it ornamental kale, and they form bold rosettes that can steal the show in autumn from your pansies or chrysanthemums.

If you grow it from seed, flowering kale can take between 75 and 90 days to mature. You want to plant them between 12 and 15 inches apart and they get up to 18 inches tall. You can find more mature plants in your local garden center. Plant them in partial shade or full sun with protection from the hot afternoon sun. When you plant them, amend your soil with organic compost. They like slightly acidic to neutral soil.

Container-Ready

Flowering kale is a very container-friendly plant. You can plant it right alongside your favorite fall plants like cordyline, pansies, heuchera, and ornamental peppers. Kale tends to look a lot better planted en masse or in containers instead of individual plants scattered about. They’re great for replacing summer flowers in your container garden, and a few tips include:

• Most flowering kale plants that arrive in pots are root-bound, and this means that they won’t grow a lot bigger. Buy the biggest plants you can find for the best show.
• Group several in containers to get the biggest visual impact.
• The brightest colors are in the plant’s centers, so arrange them so you can seem them.
• A container of flowering kale makes a nice focal point when you place it in a bed of pansies or fall flowers like mums, snapdragons, asters, sedums, or petunias.
• Keep your containers watered as they dry out faster than in the ground.

Edible, But Not Tasty

You may not know it but flowering kale is edible. If you grow them organically and don’t treat them with chemicals, you can eat them. However, you must remember that people breed them for looks over taste. The leaves will be very chewy, tough, and more bitter than edible kale, so it’s a better idea to keep the leaves intact in the garden. You can use organically-raised, clean leaves as garnish on a plate, or you can try planting edible kale varieties to grow alongside the ornamental ones, including:

• Lacinato
• Red Russian

Fantastic Borders

For instantaneous color in your borders and beds, you can buy mature plants in the fall months. Potting flowering kale tends to grow very slowly, if at all, so pick bigger plants for a big impact. Flowering kale come in shades of cream, purple, rose, and green. The colors get richer as the temperatures drop, so they’re excellent in fall gardens. Most will get around 18 inches tall and wide, so you can use them in the front of your borders and beds around other edibles or ornamentals.

Give your plants partial shade in hotter climates or full sun in cooler ones. They need well-drained, moist soil that is slightly acidic where the pH ranges from 5.5 to 6.5. After you plant them, you’ll water them thoroughly and wait until the top inch of soil dries out before you water again.

Love Chilly Weather Conditions

The stunning purples, blues, greens, and whites you get with flowering kale will help to anchor them in your garden once the night temperatures drop in the 50s. In more mild climates, they’ll look good throughout the winter months. This is because the colors become much richer when the temperatures dip below 50° and 60°F. When the weather warms back up in the springtime, the colors will start to fade. This is when your plants look leggy, and most gardeners pull them and replace them with annuals.

Most ornamental kale will last through the winter months in most areas of the country, but they won’t survive when the temperatures drop to -5°F. However, cooler temperatures discourage pests, so you won’t have many issues on that front. Powdery mildew can come up if it gets damp. Cabbage loopers and leafrollers can be an issue in more mild climates too.

Bottom Line

Flowering kale can make a statement piece in your garden if the weather conditions are right. With minimal care and the correct placement, they can create a pretty centerpiece in your garden all year-round in cooler climates.