- TEMPERATURE: 59 – 80 degrees F (15 – 27 degrees C)
- LIGHT: Bright, indirect
- HUMIDITY: Moderate
- SAFETY: Toxic to humans and pets when ingested; juice from leaves may cause irritation
- DIFFICULTY: Moderate
Dieffenbachia, also known as dumb cane, is a popular houseplant that’s been in cultivation for a long time due to its attractive foliage.
Although it’s found in many homes and offices, the plant is not pet-friendly and can cause serious damage to humans if consumed. The common name “dumb cane” stems from the plant’s ability to strike a person “dumb” if they chew the leaves.
Avoid this plant if you have curious pets or small children.
Although I would consider this houseplant moderately difficult to grow, as long as you can meet the humidity and water requirements, it shouldn’t give you too much trouble. Its well-known as a fickle plant, however, and may take some experimentation to get conditions just right.
Water your dumb cane with lukewarm (or at least room temperature) water liberally every few days in spring through fall. I usually wait until the soil is dry to the touch before watering again. You can reduce watering in the winter, but never allow the soil to dry out completely.
Insert your finger into the soil to the first knuckle. If the soil feels dry, it’s time to water (in winter). In summer through fall, keep the soil continuously moist.
Also, make sure the potting mix drains well, as standing water will cause root rot.
Dieffenbachia likes moderate to high humidity, and if the air becomes too dry the leaf edges will start to brown.
I grow my dieffenbachia near my other plants that require high humidity (including anthurium and maidenhair fern). For the best results, place the plant on a tray filled with pebbles and water, mist the air around the plant regularly, and/or place it near a high-quality humidifier.
Feed your plant with a balanced fertilizer formulated for houseplants once every two weeks. In the winter, feed only once a month.
My favorite fertilizer for dieffenbachia is Jack’s All-Purpose Fertilizer. You can read my review of this fertilizer to see why I like it so much. But in short, it provides balanced nutrients for all your plants and promotes foliage growth.
Place your dieffenbachia in a location that receives bright, indirect light. Never place it in direct sun, and avoid low-light situations or the leaf markings may fade.
A north- or east-facing window is the ideal location. If placing in an east- or west-facing window, filter the light through gauzy curtains. Avoid the harsh light of south-facing windows, or keep the plant three feet back from the glass if you must.
The plant will grow in low light just fine, but it may grow more slowly and/or become faded. If this doesn’t bother you, it’s a good solution for lower light areas (although it must get some light).
Turn dieffenbachia regularly to encourage even growth.
Dumb cane grows best at temperatures between 65 and 75 degrees F (18 – 24 degrees C). Normal household room temperatures are usually fine. Never allow the temperature to drop below 59 degrees F (15 degrees C) or dieffenbachia will most likely not recover.
Keep the plant away from drafts and heat sources (such as heating vents and wood stoves). Make sure the temperature stays stable at all times or you may have issues with leaves dropping or turning yellow.
Repot the plant in spring every other year or so, when it appears to have outgrown its current pot. Transplant to a container 2 inches (5 cm) larger than it’s previous pot. Dieffenbachia is a slow grower, so avoid planting in too large a pot.
Use any well-draining potting mix formulated for houseplants. I like this one by Happy Frog, but any good quality potting medium will work fine.
Dieffenbachia is easy to propagate. My mom always had a few cuttings sitting around in jars of water, ready to give out to friends. This was one of her favorite plants, and I have such good memories of it as a child – although I was always warned not to touch it!
The way I’ve always propagated dieffenbachia is as follows:
- Wait until the plant grows to at least 12 inches (30 cm).
- Lop off the top so that only about 6 inches (15 cm) remains.
- Remove all but the three or four topmost leaves from the cutting.
- Place the tip in a jar of water to root for 2 – 3 weeks before transplanting in a new pot.
ALWAYS WEAR GLOVES WHILE HANDLING THIS PLANT AND WASH YOUR HANDS AFTER TAKING CUTTINGS! THE JUICE FROM THE LEAVES & STEMS IS TOXIC!
Remove dust from leaves occasionally using a damp sponge or soft cloth. Remove old or dying leaves as needed.
Here are some common problems indoor gardeners have with dieffenbachia and suggestions on how to deal with them:
- Faded leaves – If the pretty markings on your leaves are fading, this means the plant is not receiving enough sunlight. Move it to an area that gets more bright, indirect light, or place it under artificial lighting.
- Brown leaf edges – If the edges of your dieffenbachia leaves are turning brown, that usually means the humidity is too low. Increase humidity by placing the plant on a tray filled with pebbles and water, mist regularly, and/or place near a humidifier.
- Yellow, droopy leaves – If the leaves are getting droopy or turning yellow, this could be a sign of over-watering. Make sure to allow the surface of the soil to dry to the touch before watering again. See my article on how to help dieffenbachia with yellow droopy leaves for more information.
- Leaf drop – If leaves are dropping, this is most likely due to low temperatures. Old leaves drop naturally with age, but if young leaves are dropping, move the plant to a warmer location.
Where to Buy Dieffenbachia
This plant is so popular, it can usually be found for purchase in grocery stores, big box stores, and nurseries. Check your local shops in spring and summer and you’ll most likely find one.
If you’re unable to find it locally (or just prefer to shop online), I would check Etsy for reputable sellers. I like buying from Etsy because you can purchase from individual growers who care about the quality of the plants.
You can also check on Amazon. Numerous large growers sell through the site. Click here to see the current selections of dieffenbachia on Amazon.