The dieffenbachia is a beautiful, if sometimes confusing, group of plants. These plants feature pointed, broad leaves in a variety of combinations of green and white. There are at least a dozen varieties, with names like D. picta, D. amoena, and D. oerstedii. A large, well-grown dieffenbachia can reach five feet, with leaves of a foot or more. However, the plants will rarely reach this size in typical indoor conditions. The so-called dumb cane gets its name from its milky sap, which is a mild irritant and should be kept from bare skin. The sap can cause temporary loss of speech.
They appreciate bright light during winter months. During the growing season, the plant prefers dappled shade or indirect light.
During the growing season, they like regular moisture and do not want to dry out. A large dieffenbachia might need to be watered twice a week. In the winter, cut back water.
Use a fast-draining, well-aerated potting mix
They like above-average warmth. If the temperature drops below 60 degrees, or the plant is exposed to cold drafts, it is likely to lose lower leaves and gain a "palm" effect.
There are several possibilities:
- During repotting in the spring, offsets can be divided (leaving some roots intact) and planted in their own pots.
- In older, leggy dieffenbachia, the top can be cut off and potted into fresh potting soil, with a rooting hormone. New leaves will sprout from the stump.
- Pieces of the cane can be sprouted by laying them horizontally in damp potting soil
These are great plants, much favored by interiorscape companies who use them either as singular specimen plants or as massed plantings to great effect. They are not, however, very easy plants to maintain over the long-term as some varieties are extremely sensitive to drafts and lower temperatures. Look for D. picta or D. amoena varieties, such as Tropic Snow, Camilla, or Marianne. Remember to wear gloves when exposure to the sap is possible, especially near the mouth. Dumb cane sap has been known to cause temporary loss of speech (hence the name).