Begonia Rex Complete Plant Care Guide

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Are you looking for one of the coolest, craziest looking plants out there? Begonia Rex is one of the most stunning houseplants, but it’s not the easiest houseplant to take care of.

Begonia Rex main care directions.

Water. Allow the top inch of soil to dry out before watering and never mist this plant.
Light. Thrives in bright indirect sunlight (south, east, or west facing windows) or under plant grow lights.
Fertilizer. Feed fertilizer in the growing season which is typically March through October.
Humidity. This plant needs high humidity in the 60%+ range.

Here’s what to know so Begonia Rex thrives in your home.

Light

Begonia Rex thrive in bright light areas of the home. An area that receives south, east, or west facing sunlight is best for this plant, but remember to never let it sit in direct sunlight.

If you place this plant near a south facing window, create some dappled sunlight by placing a sheer curtain on the window. This allows the plant to get a great amount of light while cutting down on some of the intensity of the sunlight.

East or west facing windows work as well for this plant, while north facing windows aren’t ideal since this area of the home gets very little light.

This is also a plant you can place under grow lights like T5 Barrina lights. I use these plant grow lights in my home for most of my plants and I love them.

Water

Begonia Rex need to be watered once the top inch of soil dries out. This isn’t a plant that likes to dry out.

Check your Begonia Rex by using a moisture meter or with your index finger. If the soil is dry, it’s time to give your plant a thorough watering.

An important thing to know is to never mist this plant as it can cause powdery mildew on the leaves and lead them to die off.

This plant is quite sensitive to water and must not be overwatered or underwatered. I had a bit of trouble figuring out when to water this thing and I have to admit, it was quite hard figuring it out the first month.

This is why I recommend buying a Begonia Rex as a really small plant because there’s a lot of trial and error in the beginning, and you might kill it. Eventually, you’ll figure out exactly what it needs.

Soil

Begonia Rex absolutely thrive in well draining soil. Plants thrive in settings where there’s proper oxygen flow moving around the soil, otherwise known as well-draining potting mix. You can make this kind of potting mix yourself by buying different ingredients and mixing them together or by buying a premade potting mix.

My favorite houseplant soil at big box stores is Fox Farm Ocean Forest houseplant mix. This mix comes premade with a blend of earthworm castings, forest humus, moss, and other high quality ingredients.

If you decide to make a potting mix yourself, an easy recipe is 2 parts coco coir and 1 part perlite. You can make this even chunkier by adding chunky perlite size 4 or with orchid bark.

Temperature

Begonia Rex live in temperatures between 55°F and 85°F. Do not place this plant near a drafty area like a window, vent, or door.

Fertilizer

Fertilizer is key to promoting healthy growth on your plants. Houseplants in our home can’t replenish the nutrients they need which is why fertilizing is so important. Plus, if you want healthy new foliage and large plants, you need to fertilize.

I use and recommend Dyna-Gro which is a high quality fertilizer great for any houseplant.

The NPK ratio is 7-9-5. If you’re familiar with chemistry, then you know what these are, but what they do for plants is incredible. N is for nitrogen, which is responsible for new growth on plants. P is for Phosphorous, which is for root growth and flower development. K is Potassium, which is in charge of the overall health of the plant.

Humidity

Begonia Rex is a plant that absolutely needs humidity in the 60%+ range. If you can’t give this plant that kind of humidity, I would not even bother getting it.

Increasing humidity around your plant isn’t hard at all and you’ll likely notice your plants growing healthier and happier when they have that boost of humidity.

Here are my best humidity boosting tips:

Place your plant near a humidifier that runs daily
Place your plant on a pebble tray full of water
Place your plant in a group of other plants which creates a microclimate of humidity
You may choose to mist your plant but this doesn’t do a whole lot but some people find it enjoyable

Propagation

Propagating Begonia Rex is simple. All you do is cut off a Begonia Rex leaf with part of a stem and submerge the stem in water or soil.

Place the cutting in a spot getting some sunlight and make sure to change the water once a week. In a few weeks, roots will start to show up and you can move the cutting to your preferred substrate.

Begonia Rex Common Questions

Is Begonia Rex rare?

Begonia Rex is not a rare houseplant, and in fact I found mine at one of the big box stores for less than $10.

How much is a Begonia Rex?

Begonia Rex go for less than $20 for a 4 inch pot.

Begonia Rex are generally labeled as perennials inside the home, but outside the home they are typically annuals.

How long do rex begonias last?

Begonia Rex typically has a lifespan of about two years. This is why propagating the plant and making more is a great idea.

Is Begonia Rex hard to care for?

Begonia Rex is not the easiest plant to take care of because you need to have the watering schedule just right. Not only that, this plant needs higher humidity than your average plant. This plant also doesn’t like getting its leaves wet. There’s a lot of things to remember with the Begonia Rex.

Begonia Rex can be bottom watered. Bottom watering is a great way to make sure your plant is getting all the water it needs without overwatering the plant. This also decreases the chances of getting fungus gnats.

Begonia Rex like to be root bound, so there’s no need to worry about repotting this plant all the time. Plus, disturbing this sensitive plant is not ideal as it can cause the plant to lose leaves and turn yellow.

It’s time to repot Begonia Rex when the plants rhizome starts to hit the side of the pots and bulge out. Transfer to a pot 1-2 inches larger and no larger than that.

Is Begonia Rex a fast grower?

When Begonia Rex acclimate to their new space, they can definitely be fast growers. A bright indirect sunlight spot with high humidity is ideal for this plant.

I would not put a Begonia Rex outside because this plant is quite sensitive to the elements. Find this plant a spot in your home that gets high humidity and bright light, and leave it alone.

How big do Begonia Rex get?

Begonia Rex can get fairly big, with leaves growing up to 9 inches long and 5 inches wide. This plant typically hits its growth limit once it reaches 24 inches high.

How do I make my Begonia Rex bigger?

There are a few things you can do to encourage growth on your Begonia Rex.

Regularly fertilize your plant so it gets the nutrients it needs
Place your plant in bright indirect sunlight like near a south, west, or east facing window
Consistently water when the plants soil is almost dry
Give it high humidity in the 60%+ range

Is the Begonia Rex toxic to pets?

Yes, this plant is toxic to pets. You can get more information on toxic and pet-friendly plants at ASPCA here.

Prevent pests

Begonia Rex is prone to pests, particularly mealybugs, aphids, scale, thrips, spider mites, and others. This is why I always recommend staying ahead of things by using a pest preventive.

Pests are annoying because they damage foliage and suck the life out of the plant. Having pests every now and then is just the way it goes for most houseplant enthusiasts, and that’s why pest preventive is so awesome. It really comes in handy and it’s worth it to use.

To prevent pests, here’s what you can do:

Use a natural or synthetic pest killer to prevent pests
Check your plants once a week for pest pressures
Don’t overwater your plants (overwatering can lead to increase in fungus gnats)

Bonide Systemic Granules are a great way to get rid of unwanted pests.

Common issues

Brown tips: If your Begonia Rex has brown tips, this is a sign that the plant is drying out and needs an increase of water or humidity.

Curly leaves: If your Begonia Rex has curly leaves, this is a sign that the plant is in need of water or isn’t getting enough humidity.

Yellowing leaves: If your Begonia Rex has yellowing leaves, this is a sign of many things, including overwatering, underwatering, pest pressures, or lack of humidity.

Key Points To Remember

Begonia Rex is a stunning houseplant that requires some special care, but if you’re able to care for the plant just right, you’ll be rewarded with stunning glittery leaves.

Main care tips to remember:

Place in a spot getting bright indirect sunlight (south, east, west facing windows) or under plant grow lights
Water when the top inch of soil dries out and never mist the leaves
This plant needs high humidity in the 60%+ range either with the help of a humidifier or greenhouse
Fertilize during the active growing season which is typically between March through October