Dieffenbachias can produce very impressive foliage – big, broad leaves covered with speckles and stripes of creamy white, lemon-lime yellow, and vivid forest green. Unfortunately, these houseplants often grow tall and gangly, with their gorgeous leaves shrinking or dropping off along the way. Is there anything you can do to get your Dieffenbachia to look fuller and bushier?
Dumb Canes are often kept in dim rooms, resulting in leggy growth as the plant tries to stretch toward the sun. For a denser look, keep your Dumb Cane in a brightly lit location and rotate it frequently so that it gets light on all sides. Regularly pruning the stem tips also encourages a bushier look by triggering growth from the sides and the base.
More aggressive pruning may be necessary if your Dieffenbachia has already grown too scraggly-looking. Make sure your plant has enough room to grow in its pot, and take care to provide the right amounts of water and fertilizer. Read on to learn more about what it takes to grow a robust and leafy Dumb Cane.
Normal Dieffenbachia Growth
Let’s get something clear right off the bat: it’s totally normal for Dieffenbachias to grow into tall plants with most of their leaves clustered at the top. There’s a reason they’re known as Dumb Canes and not Dumb Shrubs. If you want yours to stay short and bushy like a Prayer Plant or a Hosta, you’d better be prepared to struggle against its biology at least a little bit.
This is more true of some cultivars than others, of course. The demand for smaller tabletop-sized plants has led breeders to create a number of shorter Dieffenbachia variants. Here are a few examples:
- Camille. This is a popular and easy-to-find variety that sports big splashes of cream and yellow in the center of its leaves.
- Compacta. Living up to its name, this boldly speckled cultivar will stay below 3 feet tall.
- Rebecca. The patterning on this one looks like a cross between the cream-and-yellow of the Camille and the dots and dashes of Compacta.
- Tropical Tiki. One of the rare variants of Dieffenbachia to include silvery-gray coloring, along with small spots of deep green and bright white.
No matter what kind of Dieffenbachia you have, your care technique still counts for a lot in determining its overall shape. We’ll explain what you can do to nudge your Dumb Cane towards a more full-figured appearance.
Sunlight and Growth for Dieffenbachias
In most cases, Dumb Canes that look skinny and sad aren’t getting enough light. You can find tons of care guides online that talk about how Dieffenbachias are excellent shade plants that can survive even in dark parts of your home. What these articles fail to mention is that “surviving” can look very different from “growing large and healthy”. Dieffenbachias actually prefer very bright conditions, as long as the sunlight isn’t hitting their leaves directly.
In a dim space, your Dumb Cane will assume it’s being crowded out by other plants and respond by shooting upwards as high as it can go, creating a tall, skinny stalk. The leaves will be small, with limited variegation, and they’ll be spaced far apart along the stem.
The solution for this is simply to keep your Dieffenbachia in bright, indirect light. You should be able to read a book next to your plant without switching on a light. Just make sure that most of the sunlight your Dieffenbachia receives is reflected off of other objects in the room or softened by a partial barrier like a thin curtain.
For some helpful tips on choosing the right spot to place your plant, take a look at our article on lighting for Dieffenbachias.
Positioning and Rotating Your Dumb Cane
It’s not enough to simply pick a bright location for your Dieffenbachia and leave it there. Unless your plant is in a porch or solarium with sunlight streaming in from all sides, it will concentrate its growth on the side of its body that faces the sun. Over time, your Dieffenbachia will start to look lopsided, and it may become unbalanced as the stalk tilts toward the nearest window.
To create a more well-rounded appearance, you can give the pot a one-quarter turn every so often. This ensures that each side gets to face the light for a roughly equal amount of time. With a fast-growing plant like Dieffenbachia, you’ll want to rotate it every 3-5 days to get the most balanced appearance possible.
One good rule of thumb is to turn the plant every time you check whether the soil needs watering (see our post on keeping Dieffenbachias hydrated). If you forget for a week or two, it’s not the end of the world, but try to rotate it as regularly as you can.
Give Your Dieffenbachia’s Trunk a Workout
A wobbly stem is a problem for the robust appearance you’re trying to cultivate in your Dumb Cane. How is it supposed to look full and healthy if it’s bending over under the weight of its foliage?
Giving your Dieffenbachia lots of light helps prevent this issue, as does rotating it so that the stalk doesn’t grow twisted. But did you know that your plant also appreciates a little exercise?
In the wild, Dumb Canes grow thicker stalks when they’re pushed around by the wind. Since your home probably doesn’t get much wind blowing through it, you can simulate the effect by giving your Dieffenbachia a gentle shake every now and then.
The word “gentle” is important here – don’t thrash your plant around, just make it sway back and forth a bit. You can do this when you rotate your Dieffenbachia every few days, creating a nice all-inclusive care routine. Light agitation from a fan on a low setting can have the same effect, though try not to blow a lot of air directly onto your Dumb Cane – this can have negative effects on humidity.
Fertilize for Fuller Growth
Diet goes hand-in-hand with exercise when it comes to encouraging leafy growth. Dieffenbachias appreciate a healthy amount of fertilizer to provide the nutrients they can’t get from the sun, water, and air.
Our typical recommendation is to use a liquid fertilizer that you can mix into the watering can when you hydrate your Dieffenbachia. This allows you to be very precise with the dosage. Start with ½ the strength recommended on the package, applied once per month, then increase it little by little if necessary.
You should only fertilize when your Dumb Cane is actively producing new growth; that means it probably won’t need the extra nutrition during the fall and winter. It’s always better to err on the side of fertilizing too little rather than too much – an excess of fertilizer can encourage overly leggy growth, and may actually harm your plant.
Pruning Your Dieffenbachia to Keep it Bushy
As we noted at the top, most Dieffenbachias eventually begin to look more like a tree or a stalk of bamboo than a bush – even with precisely the right mix of sun, fertilizer, and gentle motion. Keeping yours full and rounded will most likely require some strategic pruning.
Periodically trimming off the uppermost ends of the stems will keep your Dieffenbachia’s height in check and encourage it to send more shoots out to the sides. These plants often produce multiple stalks from the same root mass. If your Dumb Cane has several stems, you can prune them to different heights, alleviating the problem of bare-looking trunks.
You can deliberately create this effect by taking cuttings from the top of the plant and rooting them right back in the same pot. This is a twist on the technique of propagating Dieffenbachias through stem cuttings, which you can read about in more depth here.
To get a cutting, slice through the stalk at a 45-degree angle, right below one of the light brown nodes that wrap around the trunk. Trim all but 2 or 3 leaves from the cut section and leave it out overnight to scab over. Then bury the cut end in the soil. Keep your cuttings humid and be very careful not to overwater them while they’re taking root.
Any time you feel your Dumb Cane is getting too tall, leggy, or bent, you can cut it back to a point where the stem is thicker and straighter to bring it more in line with your preferred shape. The more aggressively you chop it back, the more the plant will tend to branch out to the sides.
Always wear gloves when cutting Dieffenbachias, and wash your hands afterward. Their sap can cause a rash on your skin, and it results in painful swelling and sores if it touches your eyes or gets in your mouth. Before slicing into your plant, disinfect your cutting tools with a 10% bleach solution or some rubbing alcohol.
Give Your Dumb Cane Some Space
Another factor that can cause a Dieffenbachia to shed leaves and lose its vigorous appearance is an overcrowded root system. You should repot these plants roughly every 2-3 years, though the exact schedule will depend on how fast it’s growing. If you spot roots poking up from the soil or out through the pot’s drainage holes, it’s definitely time to re-home your plant.
You don’t need to increase the pot size dramatically – an increase of roughly 2 inches in diameter is usually enough. Plant it in a potting mix with lots of coarse ingredients to provide good drainage.
If you prefer to keep your Dieffenbachia in the same pot and maintain it at roughly its current size, you can give it a root pruning instead. This is exactly what it sounds like: you’re slicing away the bottom ⅓ or so of the root mass. Root pruning has a rejuvenating effect similar to cutting back the stems.
If you trim the roots back, remove a similar proportion of the leaves, because the plant won’t have the energy to support them until it recovers. Start with the topmost leaves if your goal is a bushier plant.
You can go a long way toward keeping your Dumb Cane full and bushy by making sure it gets a rich, balanced diet of light and fertilizer. The rest comes down to occasional maintenance practices like pruning and repotting. It takes a bit of effort to get the most out of your Dieffenbachia’s foliage, but the reward will be an exuberant, beautiful houseplant.