Fall annuals can breathe life into waning gardens late in the growing season, filling in among fading flowers to add beauty and interest. Mums seem to be the quintessential fall annual, although perennial in our area if established early enough in the season, packing the garden centers with blooms ranging from yellow or orange to deep red and purple.
While mums are typically planted to add floral beauty, there is also a wide array of ornamental brassicas planted for their foliar beauty, adding brilliant fall color late into the year. Unique varieties of cabbage, kale and red mustard have been developed with interestingly ornamental leaves. Many of these varieties are actually enhanced by the cooler temperatures, as nighttime temps dip below 60 degrees, gaining additional beauty and continuing to thrive down to low temperatures around 20 degrees, although some varieties remain hardy down to the single digits.
Foliar beauty is amplified by cold as these plants naturally concentrate sugars into their leaves to lower the tissue’s freezing temperature. Reds, pinks and purple-colored leaves become brighter while yellow-green, green or blue-green foliage gains a deeper, richer color with cold. The texture of foliage is enhanced as well, as curly, ruffled or wavy leaves increase character as they mature in colder temperatures. Ornamentally, these plants harbor interesting attributes that add a delightful mix of color and texture for fall.
Interestingly, all of the brassica food crops we know and the ornamental varieties came from a single species, Brassica oleracea. Everything from kale and cabbage to broccoli, Brussels sprouts, kohlrabi and cauliflower originates from a single species and are all considered cultivars of B. oleracea. The genus Brassica, which also includes the crops listed above, plus mustards, turnips and rutabaga, provides the greatest diversity of worldwide food crops derived from a single genus. Roots, leaves and flowers of the brassica family are eaten fresh, cooked and processed in innumerable combinations around the globe.
Of all the cultivated varieties of brassicas, kale is perhaps my favorite due to its wonderful productivity in the family garden. With minimal effort, it has certainly been one of our most productive crops and has worked its way into a variety of recipes and salads we enjoy throughout the growing season.
In a culinary sense, I cannot say that kale adds an overly rich flavor, but its nutritional value is hard to match. It is one of the most nutrient-dense foods on Earth, loaded with vitamin A, C and K, as well as a suite of others, earning it the informal status of “Superfood.” It serves as an excellent green and crunchy base for a salad or blends into a variety of cooked dishes as a finely chopped ingredient, almost unnoticeable to picky kids.
Botanically speaking, kale is actually a biennial plant, meaning it remains vegetative for the first year of growth and flowers during its second year. However, both culinary and ornamental varieties are normally planted as annuals.
There is wide variety of kale that does quite well in the cooler portion of our central Illinois growing season, doing best early in spring and late in fall. I would argue that many of the culinary varieties offer similar beauty to the also edible, but not nearly as tasty, ornamental types of kale.
Some of the more ornamentally interesting favorites of mine from the culinary varieties of kale are Russian Red for its beautifully purple-red stems that contrast with green-blue foliage; Winterbor, which has rich blue-green foliage that is infinitely curly, giving it a unique texture; the heat-tolerant Black Magic kale with very dark blue-green leaves that are tall and straight, having a wrinkly surface that many refer to as “dinosaur” kale leaves; and Redbor, which has similarly curly leaves to Winterbor but an exquisitely dark purple-red foliage that only gets deeper and more rich in color with cold weather.
Fall kale crops can easily be started from seed in late summer, either in trays for transplant or as direct seeding into garden beds. It’s one of those versatile crops that can really be planted about anytime throughout the growing season, although it has the best growth during cooler temperatures. I typically start fall kale plantings, which tend to do best in central Illinois, from seed around the end of July or August and plan to systematically harvest foliage from each plant until heavy frosts kill them.
Next fall, consider adding some of these wonderfully ornamental culinary varieties to your landscape in the place of ornamental kale. They will provide not only beauty but a harvestable crop that is packed with nutrition.