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Leafy, lush, and versatile, dumb cane plants make excellent houseplants. These members of the Dieffenbachia family are native to Central American and South American jungles, and the plant earned its common name because, if the stem or leaves are chewed, they will cause swelling and pain in the mouth—and, therefore, temporary speechlessness. But don't be scared: The jungle-like feel this plant brings to your home makes it well worth growing.
- Botanical Name: Dieffenbachia
- Common Name: Dumb cane plant
- Plant Type: Herbaceous
- Mature Size: 10 feet high
- Sun Exposure: Low, medium, or bright light
- Soil Type: Moist and well-drained
- Soil pH: 6.1–6.5
- Toxicity: Toxic
Plant your dumb cane in a standard houseplant potting mix. In terms of water, the soil should remain relatively moist but not soggy. Check the soil regularly, and water when the top inch of soil has dried. Dumb canes need less water in winter, and plants in lower-light conditions may also need less water overall.
To increase the humidity around your plant, group it together with other humidity-loving plants—as the leaves give off moisture, the air around the plants becomes more humid. You can also fill a tray with a layer of pebbles, and then add water to just below the top of the pebbles. Put your plant's pot on top of the pebbles, making sure that the water isn't touching the bottom of the pot. The water will evaporate, humidifying the air around your plant.
Best Growing Conditions for Dumb Cane Plant
Dumb canes do best when you're able to replicate their natural jungle habitat: warm and humid. They prefer temperatures that don't dip below 65 degrees at night, so be sure to keep them away from cold drafts. Because they thrive in moist, steamy conditions, dumb canes make great bathroom plants.
Check your plant's roots in the springtime. If they look crowded, repot your dumb cane into a pot one size larger with fresh soil.
In terms of light, dumb cane plants prefer bright, indirect light, but keep them out of direct sunlight. Certain varieties, such as 'Snow' and D. amoena, are more tolerant of low light.
Dumb canes can also survive in low-light or bright artificial light conditions, though their growth may be slowed. If you notice lower leaves dropping and your plant getting tall and leggy, that's a sign it needs brighter light.
Fertilize your dumb cane plant with houseplant fertilizer each month during the spring and summer growing seasons. Don't fertilize while the plant is dormant in winter.
Dumb Cane Plant Varieties
Dumb cane plants generally have upright stems with wide pointed leaves that are often speckled or striped with yellow or white against a green background. They thrive in warm, moist conditions and can grow in low, medium, or bright light.
Depending on the variety, dumb cane plants can vary in size at maturity. 'Sparkles,' which grows green leaves speckled with yellow, is more compact. 'Snow,' a good low-light type, can grow very high—above six feet. Take this into consideration when purchasing a plant for your space.
How to Propagate Dumb Cane Plant
After a few years, your dumb cane plant may lose its lower leaves and begin to look tall, leggy, and ungainly. When this happens, it's a good idea to propagate new plants and cut back the overgrowth. You can create many new plants from an overgrown dumb cane. The top foliage can become a new, full plant using the air layering technique.
When air layering is completed after several months, cut the stem back close to the soil level, which will cause a new plant to grow in the original pot. The long segment of the stem, or cane, in between, can be used to propagate baby plants.
How to Propagate Dumb Cane Plant via Air Layering
Step 1: Gather a sharp knife, a toothpick, a handful of long-fibered sphagnum moss, twine or twist ties, and a sheet of clear plastic like a plastic sandwich bag or a piece of plastic wrap. Rooting hormone is optional.
Step 2: Pick the spot on the central cane where you'd like the new roots to grow. This should be at least six inches below your plant's lowest leaves.
Step 3: Make an upward diagonal cut a third of the way through the stem at your chosen spot. Insert a toothpick sideways into the cut to keep it open. At this point, you can apply rooting hormone to the cut stem, which can cause roots to grow more quickly, but the process can be completed without it.
Step 4: Using twine or twist ties, tie a handful of moistened sphagnum moss around the cut. Moisten a big handful of the sphagnum moss. The moss serves as the growing medium for the new roots.
Step 5: Enclose the moss ball with the plastic, and tie the plastic to the stem above and below the ball.
Step 6: After several months, when you see that new roots have formed, take off the plastic. Cut the cane just below the new root growth. Leaving the moss around the roots, plant this new dumb cane in a new pot with fresh soil.
Step 7: Cut back the remaining stem of the original plant a few inches above the soil line, and add a few handfuls of fresh soil. This will promote regrowth. When new growth appears, care for the plant as usual.
Keep the soil moist, but take care not to overwater—because the new plant has no leaves, it needs much less water at this point.
How to Propagate Dumb Cane Plant via Cuttings
Save the leafless stem from the air layering process to propagate new baby plants.
Step 1: Prepare a tray with a few inches of moist sand. Cut a six-to-eight-inch section of cane from a healthy plant.
Step 2: Lay the section of the cane flat on the sand so that it's partially covered. Keep the sand moist. Eventually, new plants will begin to grow along with the cane.
Step 3: When the new plants are around two inches in height, cut them from the cane, and plant them in a rooting medium.
Common Growing Problems
Watch for shriveling or drooping leaves, as that's a sign your plant needs water. If you notice lower leaves yellowing or dropping, that's a sign of overwatering, which will rot the stem and kill your plant. Crispness on the edges of the leaves indicates that your conditions are too dry for the plant.
Is Dumb Cane Plant Toxic?
The dumb cane plant contains calcium oxalate, a toxin, in its leaves and stem, which causes oral swelling and pain if chewed. Because of this, be sure to display your plant out of the reach of pets or small children.
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