Plant profile: How to Care For…Dieffenbachia

This post may contain affiliate links. Read the full disclosure here.

If you’ve been hanging around this website for a while, you’ll know about my *dismal* track record with Dieffenbachia. I had one, it yellowed, dropped all its leaves, got mealybugs, and died.

To this day, I have no idea what happened. The only thing I can think is that it had root rot when I got it, and didn’t recover. If you plant looks sad, check the roots. I didn’t know that then.

If you need a refresher on root rot and overwatering, have a look at this post on helping plants recover from overwatering.

Rest assured that I have thoroughly researched this post, rather than just extrapolating from own experiences, which would go something like this:

1. Buy dieffenbachia.

2. Watch it die slowly in three ways at once

Quickfire Dieffenbachia care

  • Light: bright, indirect, to medium
  • Humidity: 40%+
  • Temperature: 18C/65F – 21C/70F
  • Watering: water when soil is dry
  • Fertilise: every 2 weeks with general-purpose fertiliser
  • Potting medium: African violet mix
  • Propagation: stem cuttings
  • Pests: aphids
  • Bloom? rarely indoors
  • Toxic? yes, very

Where do Dieffenbachia come from?

You can learn a lot about plant care if you consider where it comes from. Dieffenbachiahail from the equatorial new world – Mexico, the West Indies, and as far south as Argentina.

Where should I put my Dieffenbachia?

According to my research (though in stark contrast to my experience) Dieffenbachia are extremely easy to grow. Hmph. You can put them wherever you like, and they’ll probably survive. I mean, don’t leave in a windowless room or out in the blistering sun, but in general, they’re pretty chill plants.

Just keep out of reach of anyone likely to have a quick munch, because they’re crazy poisonous.

What kind of light do Dieffenbachia need?

Like many hardy, tropical plants, they’re not particularly fussy. Dieffenbachia will tolerate low to medium light, and grow well under grow lights.

If you really want your plant to thrive though, give it bright, indirect light.

What level of humidity do Dienffenbachia need?

It seems to be generally accepted that Dieffenbachia do fine in average household humidity, which is around 40%. If you have higher humidity levels, that’s fine too – up to about 70% and your Dieffenbachia will thrive.

How to water Dieffenbachia

Standard house plant watering practices (I have a whole watering article here) – water your Dieffenbachia thoroughly with room temperature water, until water begins to run out of the drainage hole.

Repeat only when the plant is dry. Can’t tell when your plant is dry? Get yourself a moisture metre.

Dieffenbachia are extremely sensitive to overwatering – if you have limp, yellowing leaves then check the roots before watering again. Roots should be firm and white/cream/yellow. Not mushy and brown.

How to fertilise Dieffenbachia

As with most plants, your Dieffenbachia won’t need fertilising until it’s used the reserves in the soil, which usually takes a year. After that, fertilise your Dieffenbachia once or twice a month with twice-diluted plant fertiliser. I like liquid seaweed.

Pests common to Dieffenbachia

Dieffenbachia are at particular risk from a bacteria called Erwinia. If your stems are mushy and there’s a gross smell (apparently it’s fishy), then you may have Erwinia. Chances of recovery don’t look great, but you can try cutting off the infected parts and treating the plant with liquid copper.

Apart from Erwinia, Dieffenbachia seem to be able to fend off pests themselves pretty well. They can definitely get mealybugs though, but by the time mine did it was in a sorry state, so they may only go for weaker plants.

Aphids can also be a problem – they love the new growth on Dieffenbachia. Check your plant weekly and clean the leaves with neem oil to keep pests at bay.

What potting mix do Dieffenbachia need?

According to this website, your Dieffenbachia will fare best in a soil designed for African violets, I assume because they really hate getting wet feet.

The good news is that you can buy African violet mix from Amazon, but if you want to make your own it’s pretty easy – just mix equal parts vermiculite, perlite and peat moss.

Erm, my African Violet is THRIVING in a perlite, potting mix, orchid bark mix, but i think we’ve already established that my own tips for keeping Dieffenbachia alive are not to be trusted.

I vow to purchase one this summer and keep it alive to retain a bit of credibility.

What type of pot do Dieffenbachias need?

Since Dieffenbachia are so susceptible to root rot, I’d definitely go for a terracotta pot. It will mean you need to water it more often (terracotta dries super fast) but the water won’t be hanging around the roots for long enough to rot them.

How to propagate Dieffenbachia

Dieffenbachia can go pretty big, so unless you have a massive house, you may wish to propagate parts of it, and there a few different ways you can do it.

  1. Chop off the top section. You can root it in soil or water.
  2. Cut off a piece of stem with a node in it, and plant it on its side with the node facing up – half of the stem should be in the soil. If you use a ‘greenhouse’ (a clear plastic bag will absolutely do) the process will be a bit faster. It’ll take a couple of weeks to root.

Are Dieffenbachia toxic?

Yes, very.

  • Keep out of reach of potential nibblers
  • Wear gloves when handling it
  • Thoroughly clean your equipment after e.g. pruning
  • Wash. Your. Damn. Hands.


  • Dieffenbachia are also known as Dumbcane because feeding the leaves to slaves was a common punishment. It numbs the mouth, rendering the victim speechless, and causes oral irritation, excessive dribbling, and swelling.
  • The word ‘dieffenbachia’ comes from the dude that er, named them. Somewhat self-centered. he could have picked something easier to spell.
  • They’re aroids.

Here is a Dieffenbachia Reflector I fell in love with at my local garden centre but didn’t buy because

  1. What if I’m cursed and can’t keep Dieffenbachia alive? It doesn’t deserve that.
  2. It was like £60. I need to KNOW I’m not cursed before spending that on a plant.

Caroline Cocker

Caroline is the founder and writer (and plant keeper) of Planet Houseplant

Leave a comment