The large and highly decorative leaves of Dieffenbachia make it a great favourite with interior designers, who use large ones as solitary specimen plants and smaller examplesas a key part of plant groups.
A well-grown Dieffenbachia may reach 5 ft or more, but under ordinary room conditions some of the lower leaves will fall to give a False Palm effect. It is not an easy plant to grow – it will not tolerate low winter temperatures or cold draughts. Dry air and fluctuating temperatures can be fatal to some delicate varieties, but the most popular types (varieties of D. picta and D. amoena) are fairly tolerant and not at all difficult to grow in the centrally heated home.
With age or bad management the plant may become leggy and unattractive. Cut off the cane, leaving a 4 in. stump. The crown of leaves can be used as a cutting – the stump will resprout to produce a new plant.
Its common name, Dumb Cane, is derived from the unpleasant effect of its poisonous sap on the mouth and throat. Remember to wash your hands after taking cuttings.
Types of Dieffenbachias
There is much confusion over the naming of Dieffenbachias – no two experts seem to agree! The only all-green one you are likely to see is Dieffenbachia oerstedii – look for the prominent white mid-rib. D. picta is the most popular species, bearing oval leaves with ivory white blotches or markings. These markings are variable on the variety Exotica – on Camilla, Marianne and Rudolph Roehrs almost the whole of the leaf is ivory or cream.
If you want a larger plant choose D. amoena – the stems reach 5 ft when fully grown and the leaves are 1,5 ft long. The foliage is dark green with white bars – this striped effect is most marked in the variety Tropic Snow. It is one of the best indoor houseplants despite of being a tropical plant. Unusual species include the yellow-green D. bausei and the giant-leaved D. bowmannii.
Secrets of success
Temperature: Average or above average warmth (minimum 60°F in winter).
Light: Partial shade in summer – bright light in winter.
Water: Water regularly from spring to autumn. Water sparingly in winter.
Repotting: Repot in spring every year.
Propagation: There are several methods. Remove and pot up top crown of leaves – use a rooting hormone and provide bottom heat. Pieces of stem, 2 or 3 in. long, can be used as cane cutting. Some varieties produce daughter plants at the base – remove and use as cuttings.
D. oerstedii (left), D. bowmannii (right)
Dieffenbachia ‘Tropic Snow’