Dieffenbachia — also known as the dumb cane plant — is one of the top ten most popular indoor plants out there. It’s easy to care for and has beautiful variegated green and white foliage.
Part of what makes it so easy for most people is it doesn’t need direct sunlight. The dark green leaves of this tropical plant thrive in the conditions that exist in most homes. There are so many different dieffenbachia species, you’ll find something that fits your home’s aesthetic easily.
In this guide, we’ll cover the dieffenbachia plant from A to Z – it’s care, propagation, pests, diseases, and common problems.
Let’s get started!
Quick Care Guide
|Common Name(s)||Dumbcane, Leopard Lily|
|Scientific Name||Dieffenbachia spp|
|Height and Spread||Up to 6 feet tall and 3 feet wide|
|Soil||Moist & well drained|
|Fertilizer||Feed in the growing season at half strength every month or so.|
|Pests||Scale and aphids|
All About Dieffenbachia
Dieffenbachia plants (Dieffenbachia spp.) are also known as dumb cane or leopard lily plants. They are all members of the Araceae family, or the family that includes peace lilies. These flowering perennials come from the West Indies, Mexico, and Argentina.
If left unpruned, the plant will resemble a palm tree. This is what dieffenbachia looks like in the wild. It’s here they grow on forest floors under the shade of canopy trees. Most cultivars have white speckles on the leaves, though not all cultivars have this feature.
All species grow a characteristic spadex flower (think, peace lily flower) and these tend to bloom in the wild. They may bloom in domestic environments, but it’s not as common. The flowers are white, with a spiked inflorescence. In the wild, these are pollinated by beetles.
The name “dumb cane” comes from the fact that the plant’s leaves contain raphides, which can poison you and leave you unable to speak for a period of time. Dumbcane is poisonous to humans. Ingestion can cause the mouth and throat to burn and swell. In severe cases the swelling can block airways resulting in suffocation.
According to the ASPCA, dieffenbachia is toxic to both cats and dogs. The leaves contain calcium oxalate crystals that will irritate their mouths and prevent them from performing many normal functions like swallowing.
Types of Dieffenbachia
There are over 30 different species of Dieffenbachia and over 100 different cultivars, which I can’t cover in this section. But here are a few of them stand out over the rest:
Dieffenbachia ‘Camille’ source
‘Camille’ is one of the most popular cultivars out there and probably the one you’ll see at a garden center. It’s well-known for the deep-cream color that fills the middle of each leaf. It prefers more shade than most types of dieffenbachias.
Dieffenbachia amoena ‘Tropic Snow’ source
‘Tropic Snow’ grows very tall at over 6′ tall. The leaves are similar to ‘Camille’, but less consistently cream-colored in the middle.
Dieffenbachia maculata ‘Tropic Tiki’ source
‘Tropical Tiki’ is one of the biggest dumb cane plants at 2-5′ tall and 3-5′ wide. Its leaves are silver, cream, and green and heavily variegated. It’s one of the coolest looking dieffenbachia plants out there.
‘Hilo’ is different from the cultivars mentioned above due to its lime green variegation mixed in with dark green base color. The only white found on this type is in the veins of the plant. It grows more upright at 4′ tall and just 1-2′ wide.
Because the home basically mimics the natural habitat of Dieffenbachia spp, they are not hard to care for. Here are the basic needs of this lovely tropical, and most commonly indoor plant.
Light and Temperature
Most dumb cane plants prefer a medium to bright light source. This means they shouldn’t be exposed to direct light, but will thrive 2-5′ away from a windowsill. Some cultivars prefer even less light, like ‘Camille’. You can get away with placing dieffenbachia in pretty low-light situations.
Dumb canes thrive in temperatures between 60° and 80°F (16° to 27°C). Any dipping below temperatures of 50°F (10°C) and your plant will suffer cold damage. Heat above 90°F (32°C) can cause singed leaves.
Water and Humidity
The best way to water your dumbcane is to let it get moderately dry and then completely drench the soil. Keep in mind you can only use this method if you have a drainage hole in your pot. Without one you risk causing root rot and killing your plant.
Let the soil dry to 1″ before you repeat the process and never let the soil get bone dry. In their native habitat, these plants tend to have consistently moist soil.
Like many houseplants, dieffenbachia plants need a soil that retain some water but also one that drains well. If you get a standard potting soil it may pack too tightly and drown out the roots, so mix in perlite or coarse sand to add aeration.
If you want to make your own soil mix from scratch, here’s a good recipe:
- 1 part peat moss or humus
- 1 part garden soil
- 1 part perlite or coarse sand
- 1 pinch of lime
Dumb cane loves being fed at least twice a month. Use a high quality houseplant fertilizer diluted to half strength, but make sure it doesn’t have lime. Only fertilize during the growing season — you don’t need to feed it as often (or at all) during the winter months.
Depending on the size of your dieffenbachia, it may need to be re-potted as it grows. If you decide to re-pot, do it right as winter ends and the growing season is about to start. Pick a pot that is slightly bigger than the existing pot — do not over-pot it!
Remove the plant from its original pot, and lightly dust the dirt off its roots. Pull them apart gently, and place them in the new pot, adding soil to pack it in. Water sparsely after repotting and continue your regular care regimen.
Although it’s not necessary to prune your dumb cane, you may want to trim it a bit to keep it under control. Important: Wear a good pair of gardening gloves when you prune this plant. The sap contains oxalate crystals that can irritate the skin if you have any open cuts.
To prune, cut through the stems at a 45° angle with a sterilized pair of scissors or knife. Then water your plant after pruning
There are three ways you can propagate your dieffenbachia: air layering, suckers, and stem cuttings. It can be done at any time of the year.
To air layer, cut the plant about half way through the stem with a sharp knife approximately one foot down from plant top. Place a toothpick or other thin object into the stem to hold soil mixture in place. Wrap some wet moss around the open cut and secure with plastic and rubber bands or strings. Once roots have formed, cut the new plant off below the roots and pot.
You can propagate directly from stem cuttings as long as the stem has a section where new leaves and stems will grow on it.
After you cut the stem, place it horizontally in your soil mix and bury 50% of it. The “eye” of the plant should be pointing upwards. Provide it with a lot of moisture and humidity to speed up the rooting process, which takes anywhere from 2-4 weeks.
No matter how you decide to propagate, make sure and use a sterilized cutting tool. Dumb cane is very sensitive to bacteria.
Overall, the dieffenbachia plant is a hardy houseplant that’s easy to grow. There are a few types of bacteria that can attack the plant and decimate it, so be on the watch for these.
It’s also garnered controversy due to its toxicity for humans and pets alike, but as long as you’re careful you shouldn’t have any problems having it in your home.
Dieffenbachia Growing Problems
There are a number of improper growing conditions that cause dieffenbachia yellow leaves. Moisture stress, improper lighting, and improper temperatures all are to blame. Remember to keep your plant in temperatures between 60° and 80°F (16° to 27°C) in indirect, but bright light. Water via soaking when the top inch of soil is dry.
The classic pests that affect most houseplants can also affect your dieffenbachia: mealybugs, spider mites, and aphids.
For all of these bugs, you can try to wipe them off with a cotton swab doused in rubbing alcohol. That’s an effective tactic if you catch the infestation early. You can also try washing your plant’s leaves off in water, knocking them all off. You may need to do this 3-4 times to be sure you got everything.
For more serious infestations, your best option is to go with a systemic insecticide that gets into your dumb cane plant and kills any bug that feasts on the leaves.
Most of the diseases that affect dumb cane will cause rot of some kind:
- Erwinia Blight
- Xanthomonas Leaf Spot
- Fusarium Stem Rot
- Anthracnose Leaf Spot
- Myrothecium Leaf Spot and Petiole Rot
- Phytophthora Stem, Root Rot, and Leaf Spot
While each of these diseases has their own presentation, symptoms, and prevention, there are some general rules that will prevent you from ever dealing with any of them.
Do not over-water your plant – Over-watering is the cause of many types of disease due to standing water and the rotting affect it has.
Always use sterilized equipment – When making cuttings, transplanting, and re-potting, sterilize all of the gardening gear you use to avoid transferring disease.
Frequently Asked Questions
Q: My dumb cane plant was doing fine, but now the leaves are yellowing and there are dry spots on the leaves?
A: Over time, soil breaks down and there is less aeration for the roots. If you’ve had your dieffenbachia for a while, you may want to repot with fresh soil and check the roots for signs of damage.
Q: How do I revive a dieffenbachia plant that I got as a gift? It’s not looking too good…
A: Go back to the basics — give it bright indirect light, keep the soil dry, increase humidity with misting, and keep away from hot spots.
Q: Can I root cuttings of my dieffenbachia in water?
A: For the most part, dumb cane plants don’t root well in water. They do much better with air layering or by putting cuttings in a potting soil with a lot of peat moss.
Q: Where should I put Dieffenbachia in my house?
A: Place it in an area offset from a direct light source, and away from drying AC vents.
Q: How much sunlight does a Dieffenbachia need?
A: Anywhere from bright, indirect light to full shade works!
Q: Is Dieffenbachia an air purifier?
A: Yes. Its dark green leaves will filter xylene out of the air surrounding it.
Q: Are Dieffenbachia hard to care for?
A: Definitely not. If you can remember to water and up pot these popular indoor plants, you’re doing better than most.
Q: How many times a week should I water my dieffenbachia?
A: Water when the top inch of soil is dry, which generally occurs every 1 to 2 weeks depending on the season.