Leafy, lush, and versatile, dumb cane plants make excellent houseplants. These plants in the Dieffenbachia family are natives of Central and South American jungles.
These plants earned their nickname because of the effect of calcium oxalate, a toxin in their leaves. If the stem or leaves are chewed, they will cause swelling and pain in the mouth—and, therefore, temporary speechlessness. Because of this, be sure to display your dumb cane out of the reach of pets or small children.
Dumb cane plants have upright stems with wide, pointed leaves 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 tall—over six feet. Take this into consideration when purchasing a plant for your space.
Best Growing Conditions for Your 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.
In terms of light, dumb cane plants prefer bright, indirect light—but keep them out of direct sunlight. Certain cultivars, 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 to move it to a spot with brighter light.
How to Care for Your Dumb Cane Plant
Plant your dumb cane in standard houseplant potting mix. In terms of water, your dumb cane’s soil should remain relatively moist but not soggy. Check the plant’s soil regularly and water when the top inch of soil has dried. Watch for shriveling or drooping leaves—a sign that your plant needs water.
Dumb canes need less water in winter, and plants in lower-light conditions may also need less water overall. If you notice that your plant’s lower leaves are yellowing or dropping, that’s a sign of overwatering, which will rot the stem and kill your plant.
If you’re seeing crispness on the edges of the leaves, that’s an indication that your plant’s conditions are too dry. 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, 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.
Fertilize your dumb cane plant with houseplant fertilizer each month during the spring and summer growing season. Do not fertilize while the plant is dormant in winter.
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.
How to Propagate Your 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 stem, or cane, in between can be used to propagate baby plants.
How to Propagate Your Dumb Cane 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 such as 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 plant has no leaves, it needs much less water at this point.
How to Propagate Your Dumb Cane Via Cane Cuttings
Save the leafless stem from the air layering process to make 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 cane flat on the sand so that it is partially covered. Keep the sand moist. Eventually, new plants will begin to grow along the cane.
Step 3: When the new plants are around two inches in height, cut them from the cane and plant them in rooting medium.