Like most indoor houseplants, the rex begonia is not hard to care for. In summary, it has to be
- located in a sunny or partially shaded spot,
- grown in porous soil,
- and watered until moist but not sodden.
In addition, you’d also have to feed it with fertilizer diluted to quarter or half strength every two to three weeks. This ensures that it gets the nourishment it needs to grow healthily.
For a more detailed look at how to grow and care for these plants in the best way, read this simple guide!
How to Grow Rex Begonia Plants Indoors
We have divided this section into three parts: what to do before planting the rex begonia, what potting mix is best for it, and how to grow it correctly.
Find out what you need to do for them through the advice and tips below!
What to Do before Planting a Rex Begonia Plant
- First, we advise buying a shallow pot vessel with drainage holes in them from a nursery, garden center, or florist. This will help the plant remain moist for a certain period.
- Next, prepare the rex begonia soil and gardening tools needed for the job (more on this below). You’ll need a trowel and mixer such as a plastic spoon or wooden stick.
- Then, determine the best spot to place your plant at home. Rex begonias do best in an area with full sun or plenty of indirect light.
Mixing the Right Soil for Rex Begonias
Rex begonias need a specific type of soil to thrive fully. It should be light (preferably sandy or loamy), balanced, and well-draining.
This can be achieved by mixing potting soil with peat moss or placing container stones at the bottom of the pot. These will give the plant an ideal acidic medium and encourage better drainage and moisture retention.
How to Plant a Rex Begonia
- Create the right soil mix as explained in the previous section.
- Transfer the soil to a shallow potting vessel with drainage holes.
- Sow the seed, seedling, or leaf cutting in it. Remember to give the rhizome or root ball 1 to 2 inches of space from the walls of the container to ensure they grow at their best.
- Pat and compress the soil around the cut plant.
- And water the plant until it’s moist in order to establish it in its home.
Rex Begonia Growing Needs
Now that the plant is established, you need to make sure to fulfill its growing requirements. Among them are sunlight, water, temperature and moisture, and fertilizing.
So let’s now zero in on them one by one:
Sunlight
You can position the rex begonia in a spot with full or indirect sun exposure. However, relocate it when the weather has become hot to prevent its foliage from burning or wilting.
If you let it get filtered or shaded sun, it would be best to turn the plant a quarter inch every week for all sides of the plant to get sunlight.
Temperature and Moisture Level
Native to tropical and subtropical regions, rex begonias are quite choosy when it comes to temperature and moisture level because they prefer damp and mildly warm conditions.
But don’t worry. Simply put them in an environment between 60℉ and 70℉ (15.56℃ and 21.11℃).
And as for the relative humidity, keep it at a level above 50%. If you keep the plant indoors, you can use a humidifier to reach the desired moisture level.
Watering
Watering rex begonias should normally be done once a week. This will keep the plant moist but not soaked.
Here’s a tip: water directly onto the soil and refrain from splashing water on the foliage. This will help prevent plant and pest diseases, which can be lethal to the plant.
Also, in relation to this, we advise watering earlier in the day than in the afternoon or close to nightfall. This gives the plant a chance to dry sufficiently before nighttime.
Fertilizing
Feed the plant with a well-balanced fertilizer every two to three weeks in summer, less in fall, and none in winter, which is when it becomes dormant or stops growing for a while.
Ideally, the plant food should have equal amounts of these nutrients: nitrogen, phosphorus, and potassium.
Nitrogen is responsible for healthy leaf growth; phosphorus promotes flower, fruit, and root development; and potassium benefits the overall function of the plant.
And before applying fertilizer, read the packet instructions at the back for the best results.
How to Prune a Rex Begonia
Rex begonias usually don’t require pruning, unless the rhizomes have grown large and branchy without producing new leaves.
Otherwise, you can cut back the plant to promote a lush and neat look and keep the plant stable and comfortable in the pot container.
There are times when you can obtain a cutting as a result of pruning. If that’s the case, you can propagate the rex begonia to have a new plant for your house or garden.
How to Propagate a Rex Begonia
Do you want to breed the plant? Great! Below are the steps needed to propagate your beautiful bunch of rex begonias:
- Prepare the necessary tools for propagation
Don’t just jump into the work and cut away stems and branches.
You have to sterilize the tools first in a solution. We recommend a teaspoon of bleach per quart of water.
- Take a leaf cutting from the parent plant
Get a healthy, mature leaf or leaves from the parent rex begonia. Even if they’re a little worn, it’s fine to use them so long as the underside of the leaf looks healthy and strong.
Now, once you’ve found one, cut off the portion with the leaf on it. And then, cut off the stem so that only the leaf remains.
- Cut the largest central veins of the leaf
Subsequently, flip the leaf and inspect it to find the largest veins. You will need to cut five or six of these veins because they’re exactly where the new leaflets will grow.
Using a sterilized knife, make a 1/2-inch cut across the central parts of the largest veins.
- Pin the leaf down on a seed starter mix
Now get the seed starter mix, turn the leaf or leaves over with the main side facing up, and pin the leaf into the soil using T-pins.
But be careful. Don’t pin the leaf in a way that pierces through the main veins you have recently cut. The reason for this is that new roots may not form out of them if you do so.
- Place a stone on top of the leaves
The leaves will tend to curl up, and so, to keep them in place, you can set a stone on top of them until they become a hindrance in the growth of the plant.
Remember, the leaves should be arranged in a way wherein they won’t touch each other. You can use as many leaves that will fit in your seed tray or pot.
- Give the leaf cutting light and moisture
You can treat it like a real plant now by giving it light by placing it near a window or under fluorescent lights. Additionally, locate it in a place at 70℉ and with a lot of moisture to foster its growth.
One way to do this is to cover the pot or tray in a dome or plastic wrap. For the second, though, you have to ensure it doesn’t touch any part of the leaf because this can lead to mold problems.
Furthermore, don’t forget to mist the leaves or water the soil to keep it moist.
- Watch and enjoy the leaf cutting grow
Over time, the leaves will begin to unfurl signifying new baby plants. You’ll need patience here because they can take up to six weeks to grow.
FAQs about the Rex Begonia
- How big will a rex begonia get?
At maturity, the elaborate tropical leaves of a rex begonia can grow up to 9 inches long and 5 inches wide.
However, its mound formation can expand to 12 to 18 inches.
- How long do rex begonias last?
Typically, rex begonias can live up to two to three years given that you have cared for them properly. To make the most out of these plants, you can propagate them from a mother plant, which will give you fresh, new plants to care for.
- Do begonias produce flowers?
Certain begonias do grow eye-catching flowers that are butterfly-shaped, but it can be surprising for many people that most of these plants are grown for their decorative and unique leaves instead.
- How do I make my rex begonia bloom?
You can absolutely make your rex begonias flower by practicing proper care. By this, we mean giving it partial shade, well-drained soil, and regular watering.
Besides that, feed the plant with diluted fertilizer every two to three weeks during the growing season. Also, deadhead spent blooms to promote new flower growth.
- Should I mist my rex begonia plant?
Misting isn’t necessary. Though if the weather has been unforgiving, it can be a good idea to keep the plant moist, in addition to watering it.
But be careful to not over-mist it since the plant can get excess moisture, which, in turn, will cause it to develop powdery mildew or other fungal problems.
