A varied group of plants with fleshy creeping or trailing stems, and oval-pointed leaves often zebra-striped with white, cream, purple, pink, or plum. The leaves “sheath,” or wrap their base either part or all of the way around the stem. Technical flower or other characteristics divide these plants into a number of genera. But their general appearance, habit, and culture are so similar, they are usually grouped together in catalogs and grown together in the house or greenhouse.
The commelinas can be used decoratively in a dozen different ways: in hanging baskets and window gardens; as blenders or ground covers in indoor planters, with natural or artificial light; as edgers in window boxes and other outdoor containers; as a ground cover under greenhouse benches. I’ve often used them to fill bare spots in the rock garden, in summer.
Culture simply couldn’t be easier. Ordinary potting soil and moderate fertilizing are fine. In shade the plants are full and compact; in sun the leaves color more brightly. The only problems arise from overwatering – leaves near the base of the stem turn sickly and slimy, soon wither and dry.
Pinch plants frequently to encourage branching and prevent long, scraggly growth. Pot several rooted cuttings – even a combination of varieties of different colors – in one pot or basket, for bushy plants in a hurry. When plants grow too heavy, cut out some stems near the soil, and fresh new growth will replace the old.
Stem cuttings root easily, even in a glass of water. In propagating variegated types, select cuttings with the most attractive coloring; but don’t try to root those that are nearly or all white. Creeping varieties root voluntarily, wherever the stem touches the soil.
There is nothing “common” about the commelinas. In the following list of representative varieties is a wide choice of striking patterns, colors, and color combinations. These are satisfying plants, with lively grace and a special talent for blending plants, containers, and their settings into one harmonious picture. You may find them offered under interchangeable names.
Callisia elegans (Setcreasea striata) – Well-branched creeper with overlapping, soft blue-green leaves, dapperly accented with pin-stripes of vivid white.
Callisia (Spironema) fragrans – Large, purple-tinged leaves arranged rosette-like on creeping stems that send out plant-bearing runners; flowers, white and fragrant. The variety ‘Melnikoff’ is marked with lengthwise bands of contrasting yellow.
Commelina (Tradescantia) benghalensis variegata – Dainty creeper with fresh green leaves striped with creamy-white lines; baby-blue flowers.
Cyanosis kewensis – teddy-bear plant – Tight trailer with small brown-hairy leaves, light-blue flowers.
Cyanosis somaliensis – pussy ears – Triangular, fresh green leaves with a fine fur coat, hugging tight to each other.
Setcreasea pallida – Medium-sized leaves of pure, glossy green; lavender flowers.
Setcreasea purpurea – purple heart – Large leaves iridescent purple in sunlight, the color enhanced by ephemeral white hairs; transparent orchid flowers.
Tradescantia albiflora albo-vittata – Long name for the giant white inch plant, with large blue-green leaves striped and edged with white.
Tradescantia albiflora laekenensis – Called rainbow; the most delicately colored variety with soft stripes of pale pink, orchid, white, and green.
Tradescantia blossfeldiana – Robust trailer with large, metallic green leaves lined with purple underneath, plentiful bright-lavender flowers. The variety variegata is striped with yellow, green, cream on both sides of the purple central vein.
Tradescantia fluminensis variegata – Cream-striped green version with white flowers.
Tradescantia multiflora – fern-leaf inch plant – Dark olive-green leaves tinged purple underneath. There is a tiny-leaved nana variety.
Tradescantia navicularis – chain plant – Thick, leathery gray-green leaves canoe-shaped and clasping tight to the stem; rose-purple flowers.
Tradescantia sillamontana (pexata, velutina, villosa, ‘White Velvet,’ ‘White Gossamer,’ ‘Frosty or Cyanosis veldthoutiana) – Recent introduction with shining green leaves covered with softest, silkiest white hairs.
Zebrina pendula – Large, thin leaf, the edge and center iridescent maroon or purple, separated by wide zones of silver; purple lining beneath, and purple flowers. ‘Daniel’s Hybrid’ has brown-green leaves striped with purple and silver. The variety discolor has copper-green leaves with purple and rusty zones, thin silver stripes at each side; and the discolor variety, multicolor, is an even racier version combining pink, red, cream, silver, white, and green. Another variety, Z. pendula quadricolor, is a strong grower with delicate-looking leaves. The basic color is iridescent purple-green, with bands of varying widths in gleaming white, pink, deep red, silver.
Zebrina purpusi – Heavier leaves brownish-purple, like changeable taffeta.
Common Name: Spiderwort, Wandering Jew, Inch Plant, Day Flower