PLANT OF THE WEEK

Dr. T. Ombrello - UCC Biology Department

FLOWERING CABBAGE AND KALE        

Common names:   

Flowering Cabbage and Kale, Ornamental Cabbage and Kale, and Decorative Cabbage and Kale.

Scientific  name:        Brassica oleracea

Explanation of scientific name:       

Brassica - the ancient Latin name for cabbage.

oleracea - vegetable -like.

Flowering Cabbage and Kale are ornamental versions of the cabbage and kale that we use as edible vegetables.  They have been hybridized  and selected for ornamental features including bright foliage colors and compact growth.  Growing best in cool weather, the seeds are sown in the early summer and several month old plants are transplanted into the garden in the late summer or early fall.  As the weather cools, the purple, pink or white colors of the leaves become quite pronounced.  The plants can tolerate cold weather, and in mild winters can look attractive up until spring arrives.

The name “flowering” cabbage and kale is a misnomer since the ornamental parts of the plant we value are really just fancy leaves that superficially resemble the petals of flowers.  The plants can and often will eventually produce real flowers if left in the garden.  As biennials they only bloom after experiencing winter conditions after their first season of growth.  Long stalks bearing small yellow flowers will develop when the weather warms in the spring.  The flowers are not especially attractive and the foliage is usually quite ragged after surviving the winter.  Most people remove the plants and deposit them in a compost pile long before they bloom.  

The species to which flowering cabbage and kale belongs is truly fascinating.  Wild  Brassica oleracea is native to the coastal regions of Europe, from England to Italy, and still persists there today.   The ancient Greeks and Romans grew it for food, but when it first was cultivated remains lost in history.  The diversity of form within this species, that is the result of selection over the millennia by people, is almost unmatched in the plant world.  All of the following are members of Brassica oleracea:

Cabbage, Kale, Brussels Sprouts, Broccoli, Kohlrabi, and Cauliflower.  As different as these plants are from each other, they are just variations of the same basic form.   For example, a head of cabbage is really a large terminal bud at the end of a stem, while Brussels sprouts are really side or axillary buds on a stem without a large terminal bud.  Recent DNA studies have confirmed the close relationship amongst these plants, and support the plant taxonomists who have classified  all these types as varieties of the same species.  There are some practical applications for this knowledge of plant taxonomy. If a family member will not even try eating  brussels sprouts, but enjoys cabbage or another member of this group, you can tell them with an air of authority that they are really the same species.  You might even try to convince someone that kohlrabi is just another type of broccoli.