Begonia Care Guide

All About Begonia

It’s safe to say that all indoor Begonias fall into the category of weird and wonderful houseplants. Belonging to the Begoniaceae family, this genus of perennial flowering plants boasts 2002 different plant species. The vibrant array of species can be found in moist tropical and subtropical climates scattered across south and central America, Africa, and southern Asia.  They come in many different shapes and sizes with strikingly coloured foliage and a gorgeous array of leaf forms. 

It is hard not to fall in love with Begonias! But tread carefully if you are a new houseplant custodian. 
Begonias like what they like and in most cases are unwilling to settle for less. If not cared for properly, they will not hesitate to show you that they are unhappy. But provide them with the care outlined below and they will reward you with endless beauty all year round.

Light

Finding ideal light conditions may take a little bit of figuring out. It’s always a bonus to know and understand the orientation of your home and have a good idea of how the light flows through.

Almost all Begonias will need bright indirect light. This will be essential to keeping those beautiful vivid colours. Where some species will tolerate a small amount of direct morning light others couldn’t imagine anything worse. Understanding where your choice of Begonia sits on the scale will help you to provide the perfect spot. 

Humidity

Humidity can prove troublesome and is very dependent on your home. It’s common to have varying levels of humidity that will change throughout the year depending on the season. It is highly recommendable for any houseplant collector to invest in a humidity and temperature gauge to help when picking the ideal spot.
When caring for a Begonia, it’s important to consider their native habitat as these will be the ideal conditions for your plant to thrive. Begonias will need relatively high humidity almost all year round (50-90%) but it is crucial to recreating this atmosphere in the correct way.

A lot of indoor Begonias are covered in small hair-like fibres that trap tiny droplets of water on the leaf’s surface. This drastically reduces airflow to the surface of the plant and can result in powdery mildew and fungal infections if not dried out quickly enough.

The average home has a humidity level of 40% and most Begonias will tolerate this.  But keep a close eye on stress signals from your plant. If you cannot figure out why your plant is struggling, it may be time to consider its humidity levels. This can affect plants much quicker in the winter when the central heating is fired up and removes all of the precious moisture out of the air.

The best way to maintain high humidity is to use a humidifier placed about a metre away from your plant (so droplets do not form on the leaves) to provide high ambient humidity.

Alternatively, you could place your plant on an undertray filled with clay pebbles or small stones that are sitting in a shallow layer of water.  Make sure the plant is not submerged in any water as this can lead to root rot.

As the water from the undertray evaporates from the surface of the pebbles or stones it will keep humidity levels high exactly where you need it most.

Water

Watering Begonias can be difficult.  The number one killer for these plants is too much water.  There is a fine balance between keeping the soil damp rather than wet and then allowing enough time for the soil to dry out. 
There will also be factors within your home that will contribute to how quickly your plant will dry out. This means that watering can be very subjective depending on the location within your home. For example, if it’s in a dry environment e.g. next to a radiator, it is likely to dry out quicker than if it was placed in a nice, humid bathroom.

Soil

Begonias require free-draining and airy soil. They like to have a bit of space around their root for maxim airflow.

Most houseplant composts will do the job. However, you can further increase the aeration of the soil by adding perlite to your mix. In my experience, a ratio of 4:1, 4 parts houseplant mix to 1 part perlite, works wonders.

Did you know we make our very own houseplant potting mix? Check it out here!

Pests & Disease

Pests are the bain of all houseplant lovers’ lives. They seemingly appear out of nowhere and proceed to sap all the goodness out of our leafy friends.

Unfortunately, this is no different with Begonias. It is good practice to regularly check your plants for any signs of aphids, red spider mites, mealy bugs, and thrips. You may notice some signs of distress and allow yourself time to prevent a full-blown attack. 

With Begonias being such lovers of humidity this can leave them susceptible to powdery mildew and fungal issues. These will mainly occur if they have been overwatered, leaves misted, or if they have not been able to dry out in time.  Powdery mildew is an easy problem to spot, it stands out very clearly on the bright foliage. But the fungal issues will generally lead to leaf curl and yellow/brown spotting. To treat powdery mildew, prune away the affected leaves and keep the plant in a room with a stable temperature and humidity. If the problem persists, treat with a suitable fungicide.

Check our video on homemade pest remedies or head over and read are Fungus Gnat Fact Check

Feed

Begonias prefer high potassium plant food. This will help to build stronger plant cells, allowing the plant to withstand stress much more effectively. This will help give your plant the best chance to thrive!

Repotting

The appropriate pot size will depend on the variety of your Begonia. The two main types of houseplant Begonias are; 

Crane Stem, otherwise known as the Angel Wing variety, has much more fibrous roots and will prefer deeper pots so they have space to extend their root system. 

Rhizomatous Begonias, for example, Rex Begonias, grow from horizontal rhizomes under the soil instead of a normal root sy