Dieffenbachia plant pronounced (deef-en-BOK-ee-uh) known also as the “Dumb Cane” makes an excellent tropical houseplant. “Dieffs” tolerance of shade makes them a good plant to begin learning the basics of indoor houseplant care.
In this article, we share tips on common indoor Dieffenbachia plant care along with, answers to some of the most common questions on “dumb cane” regarding:
- How poisonous is the dumb cane plant for cats, dogs, and children?
- How to on propagation
- What to do when plants get too tall
- Leaves turning yellow
- and much more
Let’s get started!
Quick Dieffenbachia Care Guide
- Botanical Name: Dieffenbachia – (deef-en-BOK-ee-uh)
- Common Name(s): dumb cane,
- Family & Origin: Araceae – New World Tropics, Mexico, West Indies south to Argentina
- Growability: Easy to grow
- Grow Zone: USDA hardiness zones 10-12
- Size: Small varieties 12″-24″ inches | Tall varieties up to 6″ feet tall
- Light: Medium to high light (bright east or south window)
- Temperature: 70°-80° degrees Fahrenheit – damage occurs below 50° degrees Fahrenheit
- Soil: Plant Dieffenbachia in a houseplant potting soil or DIY two parts peat moss and 1 part perlite.
- Water: Keep the potting soil moist, can tolerate some soil drying.
- Fertilizer: Apply a liquid houseplant fertilizer at 1/2 strength every 6 weeks to 2 months.
- Pests & Diseases: mealybugs, spider mites
- Propagation: Tip cutting or stem segments
- Toxicity: Sap is toxic, causes inflammation and burning sensation to skin. Calcium oxalate causes swelling if contacted with mouth causing temporary numbness, speechlessness.
- Grooming: Wipe leaves monthly with a damp cloth to remove dust.
- Uses: Display on a tabletop, large varieties use as a floor plant
Why Is The Dieffenbachia Plant Called “Dumb Cane”?
The common name for Dieffenbachia is “dumb cane.”
Through the years the plant has also been known as the mother-in-law tongue (the common name used for Sansevieria aka “snake plant”) referring to the toxic sap with calcium oxalate crystals, which inflame the tongue and throat causing temporary loss of speech if ingested.
Where Did The Name “Dieffenbachia” Come From?
The name Dieffenbachia was given to the genus by Heinrich Wilhelm Schott the director of the Botanical Gardens in Vienna to honor the head gardener Joseph Dieffenbach (1796–1863).
Schott was a botanist well known for his extensive work on the aroids (Family: Araceae). [source]
The herbaceous perennial dumb cane plant originates from the New World tropics rainforests of Mexico to Argentina and the West Indies.
The plant has alternate simple leaves with white flecks or spots attached to straight stems. The native origin provides some idea of the type of care and conditions the plant likes.
Are Dieffenbachia Plants Poisonous?
Yes, the dumb cane is poisonous and toxic, causing swelling of the throat and skin irritation, and more.
Does The Dieffenbachia Flower?
After flowering, the center of the Dumb Canes stem “dies” but side shoots usually form, and the plant continues to grow. As the side shoots mature they can be removed, propagated and planted to produce new plants.
What Is Dieffenbachia Amoena?
Dieffenbachia Amoena is the plant most people commonly know of all Dieffenbachia plant varieties.
It is one of the taller Dieffenbachia varieties growing to heights of around 4 or 5 feet as large single stem specimens and floor plants.
The thick-stems support long, dark green mottled foliage, pointed oblong leaves which ascend spirally around the canes.
A sport known as Dieffenbachia ‘Tropic Snow’ has been grown and sold as a common indoor house plant for decades.
The World Checklist Of Selected Plant Families at Kew Gardens currently lists 56 “accepted names” dating all the way back to Dieffenbachia seguine in 1832. There have been additions and Dieffenbachia discoveries in the last 30 years by Croat at the Missouri Botanical Gardens and others.
Interestingly, as popular as Dieffenbachia Amoena is, the plant IS NOT an “accepted” species.
How Do You Care For A Dieffenbachia Plant?
The Dieffenbachia is a hardy plant and will reward you with a long lifespan if properly cared for.
In terms of difficulty and its requirements, it is one of the easiest indoor houseplants you’ll ever have the pleasure of caring for and maintaining. It grows no matter the month or season.
How Big Does Dieffenbachia Get?
The answer to plant size depends on the variety.
Dieffenbachia has given us a long list of handsome available foliage plants with dozens of named species, variants, and hybrids. The list grows as more varieties appear each year.
The larger varieties like Dieffenbachia amoena ‘Tropic Snow” grow 4 – 5 feet tall and can easily be 48” inches in width. This requires the plant be planted in larger pots (14” inches or more) for the plant to not become too top heavy.
The large varieties make perfect additions for indoor spaces with lots of room.
The smaller almost dwarf Dieffenbachia varieties like ‘Compacta’ as the name implies grows to only 24” – 28” when mature.
The one difference is the smaller dumb cane varieties have a tendency to sucker heavily producing a very bushy plant. They also have a much more natural mottling of white or yellow colors present in the leaves.
The smaller varieties are often times sports or variants. For example, Dieffenbachia Camille comes off a ‘Compacta’ variant, with cream-colored or white leaves that exhibit thin, green strips on its borders.
Some of the smaller dumb cane plant varieties to look for at the garden center include:
- Dieffenbachia Camille
- Dieffenbachia Compacta
- Dieffenbachia Delilah
- Dieffenbachia Exotica
- Dieffenbachia Sparkles
- Dieffenbachia Star Bright
- Dieffenbachia Tiki
Dieffenbachia care is the same for both large and small varieties.
How Much Light Does The Dieffenbachia Plant Need?
Dieffenbachia does well in a semi-sunny to a shady location and does not need much sunlight.
The plant will, however, thrive in bright light conditions. Dumbcanes do well when grown under artificial plant lights.
Bright light does make the ordinarily dark lush growth and color; the Dieffenbachia is known for to become dull.
Dieffenbachia can grow outdoors with lots of sunlight but needs protection from wind and the hot noon sun of summer or plants begin to look sickly.
Too much sun will burn the leaves, but too much shade on the heavy white/yellow varieties will cause them to be poorly colored.
What Is The Best Temperature For Dumb Cane Plants?
The Dieffenbachia plant does well as a houseplant, thriving with year-round average room temperatures of 65° – 75° degrees Fahrenheit. Dieffenbachias will not tolerate low temperatures.
Anything below 60° degrees Fahrenheit and growth begins to slow. Some varieties start to show cold damage when temperatures fall below 55° degrees Fahrenheit.
In fact, high temperatures and bright light can make Dieffenbachia weak and sickly.
How Often Do You Water Dieffenbachia Plants?
Being from the aroid family Araceae – with cousins like the “Chinese Evergreen” (Aglaonema), “Peace Lily (Spathiphyllum)” and Philodendron – lets us know dieffenbachia likes humidity.
As for watering, we recommend to water your dumb cane thoroughly and allow the soil to thoroughly “approach dryness” between waterings.
Watering Dieffenbachia indoors is somewhat of an art form. There is no exact schedule. You need to consider the location, time of year, soil type, lighting and humidity which all contributes to – How often you should water any dumb cane houseplant.
Plants often need more water during the summer seasons and less during winter time. The growth cycle of this plant starts in March and ends in October.
Too much water (overwatering) may drown the fleshy roots, or cause rank, weak growth, and stems to become mushy.
What Is The Best Soil For Growing Dieffenbachia Plants?
A potting soil mix used to in African violets care would be fine.
You’ll often find recommendations such as:
- One part all-purpose loam
- One part peat moss
- One part sharp sand, perlite or vermiculite.
Growing Dieffenbachia outdoors on an open shaded patio the above soil mix may work well.
When growing indoors as a houseplant, purchase a houseplant potting soil or make your own with two parts peat moss and 1 part perlite. Keep it simple.
Potting Tips: When potting or repotting plants, springtime is best just before the growing season begins. Do not overpot!
Dieffenbachia Pruning and Grooming
There is no need to ask “When to prune your Dieffenbachia” as it does not need grooming or pruning! Older leaves will yellow and need removing, but other than that little “grooming” is required.
How To Propagate Dieffenbachia Plants
Propagating plants gives the homeowner a simple way to increase their collection. If your dumb cane has grown too tall, why not try propagating your Dieffenbachia.
Dieffenbachia Pests and Diseases
Why Is My Dieffenbachia Leaves Turning Yellow?
Yellowing leaves come with several possibilities.
If your plant has is healthy and one or two dieffenbachia yellow leaves show up throughout the course of the year it is most likely an old leaf.
The older lower leaves on a dumb cane plant naturally die once they reach about one year old. If the plant is experiencing more than the occasional leaf dying off, a more serious problem may be starting to show.
Massive yellowing and dropping of leaves including:
- Curled leaves curl
- Leaf tips turning brown and dying back
- Plant rotting, wilting and bleached foliage
- Weak new growth
Overwatering usually causes these conditions. Follow these steps to try and help the plant recover.
- Remove the plant from the pot
- Make sure the drainage holes are not clogged
- Check the roots for health.
- Roots should be white and free from any disease or rot.
- Remove any damaged roots
- Plant Dieffenbachia in the right soil
- If the root system looks good, and only a few roots need removing put the plant back into the pot, add new soil if required or repot using fresh soil.
- Remove all bad or damaged leaves
- Place plant in a well-ventilated area
If after removing the plant from the pot the roots are mushy and soft the plant will likely not survive. Take any tip and stem cuttings possible and follow the propagation tips above.
Throw the old plant out including the soil.
The Dieffenbachia is a tough plant whose one weakness is bacteria (Erwinia). The plant will exhibit rotting leaf joints that will spread throughout once it’s infected. Rotting can also start on the stem.
Once infected there’s very little you can do to save the plant. Pots can be reused, but take the proper steps to disinfect it before reuse.
What Causes A Dieffenbachia To Have Brown Spots On Leaves?
The Dieffenbachia does like humidity and does not like cool temperatures. When plants experience a sudden chill and too much humidity a fungal disease known as anthracnose can develop.
The leaves will have black or dark tan spots in the center and dark, narrow margins. Leaf tips or margins become brown and die back.
- Remove and destroy these fungal infested leaves
- Keep plants on the dry side
- Keep plants in a well-ventilated area
- Spray healthy plants with a fungicide (neem oil) to stop the spread of the disease
NOTE: Most homeowners will never experience the anthracnose problem with their plants indoors.
Brown Spots On White-Patterned Dieffenbachia Varieties
During the winter months, plants are not in an active growth phase and the need for water and fertilizer is lower.
Leaves on white-patterned Dieffenbachia varieties – Compacta, Camille, Exotica, etc. – can exhibit dry brown spots during the winter caused by the soil staying too dry or too much fertilizer.
During winter months – DO NOT allow the soil to dry out completely and DO NOT fertilize!
Why Are The Stems and Roots Rotting On My Dieffenbachia?
When plant stems and roots turn soft and mushy at the base it’s known as – stem rot and root rot.
This is a fungus disease (Fusarium) caused by several conditions:
- Too much humidity
- Temperatures too high
- Temperatures too low
Take the following steps to rescue the plant:
- Remove the plant from the pot
- Remove all soil
- Remove all infected areas – leaves, roots, and stems
- Treat all wounds with a fungicide
- Repot in fresh soil and a new pot (recommended)
- Allow soil to dry well before rewatering
- Keep the plant the proper growing conditions.
Top Down Stem Rot
Stems can also rot from the top down. What are the signs?
- Curled leaves
- Discolored foliage
- Soft foliage
- Leaves with brown edges
These “plant alerts” are caused by cold drafts and cold temperatures.
To combat top down stem rot take the following steps:
- Remove all infected areas
- Treat all wounds with a fungicide
- Move the plant a warmer location
NOTE: These spots aren’t caused by bacteria and will appear withered as compared to a rotten and smelly when they are infected.
Why Is My Dieffenbachia Having Distorted Leaves? (Dasheen Mosaic Virus)
Distorted leaves are often caused by the Dasheen mosaic virus. The virus is more common on select Dieffenbachia cultivars.
Symptoms include distorted leaves and stunted plants. Aphids and man commonly help spread Dasheen mosaic virus. Today most pathogen-free Dieffenbachia stock is produced my tissue cultured micro-cuttings.
No chemicals can control this virus disease. Monitor other plants such as Aglaonema, Spathiphyllum, and Philodendron for symptoms, as they can act as a host and reservoir for the virus. [source]
How To Control Mealy Bugs, Spider Mites, And Aphids On Dieffenbachia
The indoor conditions – warm and dry – during winter months make a perfect place for spider mites to set up shop on the underside of leaves and feed – sucking the juices out of your plants.
Any time of the year those cottony, sticky looking pests mealybugs hiding in clusters in leaf axils and on stems, even venturing to the root area. They also enjoy feeding on your Dieffenbachia.
Aphids enjoy sucking the juices and feeding on new growth during the active growing season.
To control these Dieffenbachia pests:
- Examine your plants weekly – all the way down to where the leaf meets the stem
- Clean and wipe the tops and bottoms of leaves
- Use sprays designed to control the insect pests such as Malathion or garden safe Neem oil for plants. – mealybugs, spider mites, aphids (homemade control) and other pests.
Organic Neem OIl 100% Pure Cold Pressed – (16 oz) – OMRI Listed for Organic Use Price: $16.99 Neem Oil is our FAVORITE natural organic insecticide. Control aphids, mealybugs, plant scale and more. It can also be used as a soil drench.
What Are The Most Popular Dieffenbachia Varieties?
The Dieffenbachia aka Dumb Cane plant – has been grown and available as a houseplant for decades. Over that time many varieties have come and gone.
The varieties available break down into two groups based on their size – large floor plants and smaller “table top” selections.
Large Dieffenbachias – Floor Plants
These large varieties make striking individual specimens indoors if you have the real estate or outdoors on a covered patio for example.
The plants can reach heights of 4 – 5 feet if allowed. However, indoors a plant 30” – 42” is more the norm.
The most popular large varieties are:
Dieffenbachia Amoena as discussed above. There are also various sports of “Amoena” available. The most popular or well known patented variety is “Tropic Snow” PP 2,869.
“Tropic Snow” was discovered in the 1960’s as a sport in a block of Dieffenbachia amoena growing at Chaplin’s Nursery in Fort Lauderdale, Florida, according to US Patent Office records. I actually visited the nursery many years ago.
A patent for the plant Dieffenbachia amoena cv. Tropic Snow Plant Patent 2,869 was issued on February 25, 1969. It was the first Dieffenbachia to receive a patent.
The “discovery” document filed at The United States Patent Office August 14, 1967:
Small Dieffenbachias – Tabletop Plants
There are many more smaller dumb cane varieties available on the market and many are produced from tissue culture microcuttings. Below are several well known varieties growing in size from 18” – 30” inches.
Well-grown plants have stout stems, completely hidden by the bases of the leaf petioles where they clasp, but exposed below, where older leaves have fallen.
Dieffenbachia ‘Alix’ is a sport of ‘Tropic Snow’ with white and green variegated leaves but smaller and suckers well. [source]
Dieffenbachia ‘Camille’ – bushy grower reaching 20 inches tall, creamy white leaves with green midrib and borders. more
Dieffenbachia ‘Camouflage’ pp#12275 – A plant mutation of the not patented Dieffenbachia sp. cultivar ‘Panther’ (Dieffenbachia Panther). Characterized by large leaves with unique and attractive variegation pattern. Freely clumping, full, dense plants with an upright growth with an outwardly arching growth habit.
Dieffenbachia ‘Compacta’ – like ‘Camille’ growing to 22 inches tall with green spots.
Dieffenbachia ‘Memorii Corsii’ – carries Silver-like marking with a moderate branching habit. Memoria Corsi has been around for almost 150 years.
As described in the 1871 The Garden: an illustrated weekly journal of gardening in all its branches
Found in the Spring Flower Show In Paris. The show of the Paris Horticultural Society
“M. Dalliere, of Ghent, the only foreign exhibitor, showed a small group of new plants, including Dieffenbachia memoria Corsi.” [source]
Dieffenbachia ‘Nelly’ – small, well branching, compact slow growing with cream and green leaf variegation. Often used in dish gardens or small 6-inch pots.
Dieffenbachia ‘Panther’ – A fast-growing plant, large dark green leaves with wide silver streaks etched down the mid-rib. Additional lighter green random “spots” decorate the leaf blade. Leaves can reach lengths of 24” long and 10″ wide.
Dieffenbachia ‘Parachute’ – Medium sized plant, with white creamy variegation sitting atop dark green foliage. Beautiful green with yellow speckled leaves.
Dieffenbachia ‘Perfection’ – a variety like ‘Compacta’ with cream and green variegation and larger leaves.
Dieffenbachia ‘Rudolf Roehrs’ – holds leaves are gold-green with white blotches, dark green leaf edges, and midvein.
Dieffenbachia ‘Splash’ PPAF – A hybrid from Oglesby. An upright, fast grower with a good branching habit.
Dieffenbachia ‘Star Bright’ – Dark green margins on cream-white foliage with speckles dark green speckles. Long, narrow leaves, unlike most other Dieffenbachia varieties on the market.
Dieffenbachia ‘Sterling’ pp #14762P2 – Compact, well-branched plants with averaging 4-8 basal shoots per plant. Very deep green leaves highlighted with dramatic white midrib extending from the leaf base to the leaf tip creating a herring-bone pattern.
Dieffenbachia ‘Tiki’ pp #7298 (expired) – Deep green margins on the leaf edge with light green venation fading to dark with bright white spots. This sport or cultivar was discovered at Vanderlaan’s Nursery, Inc., Lake Worth, Fla. from a population of asexually propagated Dieffenbachia memoria Corsii plants. [source]
Dieffenbachia ‘Triumph’ – creamy white leaves with green border and a pink cast at the petiole base. Grows to 22 inches tall.
Dieffenbachia ‘Tropic Marianne’ pp #8832 – characterized by a dense upright branched habit and yellow-green oblong leaves bordered with green.
Dieffenbachia ‘Wilson’s Delight’ – large solid-green leaves with a white mid-vein.
Learn about dieffenbachia hybridization at the University of Florida.
What Are The Best Uses For The Dieffenbachia Plant?
The larger Dieffenbachia varieties make excellent floor plants. Make sure to place them in locations where people traffic is low. Also large plants can topple over if they get top heavy or dry out when placed in areas where they may experience drafts.
Smaller varieties which reach 24” to 30” inches tall can also can also function as floor plants. Other can make great additions as single specimens in an attractive decorative pot on a desk or credenza.
Smaller Dieffenbachia varieties make good bathroom plants with the high humidity found in bathrooms.
Wrapping Up Dumb Cane Plant Care
For the best look, thriving Dieffenbachia plants should have a bushy shape with a compact frame, full, glossy leaves and a healthy and succulent appearance.
Even with the “downside” the Dieffenbachia plant is a wonderful addition for indoor use and brings a real tropical look to any interior.