Nutritionists tout kale because it is loaded with calcium, iron, vitamins A, C and K, and it has phytonutrients. Chefs enjoy its texture and versatility. Gardeners love it because it is easy to grow and because it likes the cooler temperatures. And, this time of year, many types of kale have the added bonus of bringing a burst of color to the garden.
Many garden centers and nurseries are currently offering a selection of ornamental kale. Genetically the same as culinary kale, ornamental kale doesn't taste as good but is great as a fall and early winter landscape plant. All kale is part of the Brassica family of plants, which includes broccoli, cauliflower, cabbage and Brussels sprouts. Kale's leaf color and sweetness intensifies in cooler temperatures, and in some areas of the country, you can overwinter your kale to yield an early spring harvest.
Ornamental kale is actually a biennial, which means it produces foliage the first year and flowers the second. It is also often grown as an annual for its attractive foliage. Ornamental kale's leaves form a tight, attractive rosette, and they can have curly, ruffled or even feathery textures, depending on the variety. Outer leaves are usually a blue-green shade, and the centers can turn red, purple, pink, green, yellow or ivory as they lose their chlorophyll.
Sometimes ornamental kale is sold under the name "ornamental cabbage," but this term is technically incorrect. While both plants feature bright colors, ornamental cabbage forms a head and has broad smooth leaves. Ornamental kale, however, does not form a head and has dissected, ruffled leaves.
The deep colors of ornamental kale intensify when nighttime temperatures dip below 60 degrees Fahrenheit for a few weeks or more, and the plants can continue to thrive in temperatures as low as 20 degrees. They even have been known to survive cold snaps with temperatures as low as 5 degrees if they have been acclimatized.
If you are considering adding some colorful ornamental to perk up your garden, here are some tips to get the best mileage and enjoyment out of your plants.
First, hold off on planting until the nights cool off in your area. Ornamental kale likes things cool and it can get leggy and faded in a hurry in the heat. Another reason to wait is that pests, such as cabbage loopers and aphids, will be more of a problem in the heat.
Secondly, look for plants that are not root-bound. If the plant is struggling in the container in the nursery, it will not grow in size when you plant it in your garden or larger pot. Look for large plants with short stems and leaves that are somewhat uniform in length. Check that there are not holes in the leaves and that there is a hint of emerging color, realizing that the color will intensify in cooler weather.
Next be sure to plant the kale in moderately moist soil in a spot where it will get full sun. Be careful not to over water. Kale likes to dry out between watering, but it will get stressed if left without water for too long. Kale prefers a slightly acidic soil with a pH in the 5.8 to 6.5 range. If you are planting in a container, look for adequate drainage. If you are planting in the garden, plant the heads 10 to 12 inches apart.
As nighttime temperatures cool down, kale plants are relatively pest-free. Powdery mildew can be a problem if the weather is damp, and be aware that animals such as deer and rabbits find them quite tasty.
Ornamental kale looks great in a pot on your doorstep, along your front walkway and as a dramatic and colorful accent to your fall and winter landscape.