Dieffenbachia, or Dumb cane, is a plant indigenous to South and Central America. It was named to honor the chief gardener of the Vienna Botanical Gardens, Joseph Dieffenbach. It is popularly cultivated indoors as an ornamental houseplant and grows well in soil or water.
It is a fast-growing, attractive plant with straight stems and alternating green leaves that are often variegated with cream and white spots/streaks and is very tolerant of shade, making it an ideal indoor plant to cultivate.
It also produces flowers that look similar to peace lilies, although the flowers are not as attractive. It can reach almost 10 feet tall with 20-inch leaves outdoors, although 5 feet in height is usually the norm indoors, the height is dictated by the size of the pot.
It grows well in indirect bright lighting settings as well as under varied lighting conditions, although the plant grows slower in low lighting conditions. Avoid keeping the plant in direct sunlight, particularly at mid-day as the leaves will get burned.
Dieffenbachias can survive with artificial lighting conditions of commercial window-less buildings as long as there is enough light.
It prefers to be watered well, drying out a bit prior to the next watering, usually once a week. It needs more watering in its growth period during the warmer months and less in winter.
The plant doesn’t usually have a problem with low humidity, although it might attract pests in low humidity.
It prefers temperatures to be between 60°-80 °F and not lower than 50°F as leaves might start dropping and growth will become slower.
It’s best to feed it once a month with a half-strength all-purpose liquid fertilizer diluted in 4 quarts of water, although some gardeners prefer to feed it at every watering.
It thrives in loose, aerated, and well-drained soil mix in a pot with good draining capabilities. The roots might suffer damage in moisture-retaining soil.
Caution should be taken by not releasing the toxic sap by damaging the leaves and always use gloves for protection against exposure.
It will benefit from being repotted once every 2 years or so, replacing the soil with fresh potting mix. You can trim the roots if you’re reusing the same pot.
This will help keep the plant healthy. Repot into larger pots only if you want the plant to grow taller – use the same pot if you want the plant to stay the same size.
Avoid exposure to the toxic sap by always use gloves when pruning.
Pruning is normally done to remove dead leaves and to make the plant look healthy and attractive. The plant will also need to be pruned when it grows too tall and leaves start dropping off, exposing the stem.
Cut the stem off about 6 inches above the soil, near a leaf node – use a saw if the stem is tough to cut. Note: save the cuttings for propagating new plants.
It is typically propagated in three ways – cuttings, suckers/offshoots, and stem shoots.
Divide the canes you just pruned into 2-inch cuttings, with a node just above the bottom, and remove most of the leaves. Leave just one, cutting the leaf in half so it won’t affect root development.
Use a suitable glass container (if you’re growing it in water) to observe root development and water levels, tinted if possible to prevent algae from growing.
Change the water fortnightly or if you notice it becoming discolored, making sure to clean the container well.
The cuttings can be transferred to the soil once the roots appear or the new plant can continue to be grown in water – feed it with a few drops of liquid fertilizer once a month.
If you prefer to grow it in soil, plant the cuttings covering the node in a well-draining potting mix and water thoroughly. The soil has to be damp but not water-logged. Roots will take about 2 months to start showing and for new leaves to appear.
These are new plants that appear in the soil near the roots. Remove these and plant as with cuttings.
These are propagated from a part of the stem with leaf buds. Cut off the stem and place it horizontally in a pot, partially buried in the soil with the leaf buds pointing upward. Rooting will begin in a few weeks.
It should not be exposed to cold drafts as the leaves will curl and turn yellow. Rotate the pot regularly to encourage healthy and even growth. Clean the leaves to remove dust and/or pests – make sure to check for pests/damage while doing this.
You might encounter stem and root rot because of overwatering. Occasionally, the rot can be so damaging to the plant that it can kill the plant. Cut off the healthy part of the cane and propagate it, if this happens. Make sure to follow your watering schedule and that the soil is not water-logged.
Over or under watering can result in the edges of leaves becoming brown. Monitor the soil and water the plant properly.
Too much light can result in leaves turning pale or getting leaf burn. Move the plant to a better location.
Leaves naturally die and fall off but this happens to several leaves at once, it indicates that the plant has been exposed to low temperature or is constantly exposed to cold wind.
Dumb canes are sometimes attacked by insects like scale, aphids and spider-mites can still attack plants. Use Neem oil to control any pest infestation.