Rex Begonia Care: Everything You Need to Know

Rex Begonia Care: Everything You Need to Know

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We all have that friend who is very effective yet annoying and hard to deal with. Unfortunately, this description perfectly fits the rex begonia plant as it has a reputation of being demanding and tricky to cultivate. With rex begonia, though, efforts are well worth it when it produces its flamboyant, attractive, and decorative foliage to your delight.

Having over 2000 different species in their family, Begonia plants are globally recognized for their beauty and ornamental value. Additionally, rex begonia is regarded as the ‘kings’ of the Begonia world. Some even call them the showboat of the Begonia world. The reason is because of their outstanding beauty. 

Stick around as I show you everything you need to know about caring for the exceptional rex begonia.

Does Rex Begonia like Sun or Shade?

Did I tell you that rex begonia originated from Assam in northern India? Well, now you know. This information gives insights into what enables rex begonia to thrive as a tropical and subtropical plant.

Rex begonia thrives best in bright indirect sunlight. They also perform well under direct sunlight if the intensity is mild and gentle. However, chlorophyll is only a secondary pigment in rex begonia. The dominant pigments in the plant are only tolerant to sunlight.

Furthermore, any intensity of sunlight that does not discomfort you is sure to benefit the rex begonia. So, you can place an indoor rex begonia close to an east window to give it a feel of the gentle morning sunlight. Outdoors, place the plant under a mild shade where it can get glimpses of sunlight now and then.

The light requirement is one tricky aspect of rex begonia’s care. Poor lighting can cause stunted growth while excess light at high intensity increases transpiration resulting in crispy brown leaves. Alas, here is a shortcoming that comes with the broad foliage and flat leaves: excessive transpiration. Read on and see another tricky aspect – moisture!

How Often Should You Water Begonia Rex?

Rex Begonia Care: Everything You Need to Know

Ideally, rex begonia is watered sufficiently once every week and about once every two to three weeks during winter. However, it would help if you carried out watering once the soil is dry to touch. This should be the guiding principle for watering rex begonia, i.e., how dry the soil has become.

The reason for this principle is that an effectively porous soil can rapidly drain out water, and evaporation could speed up anytime. Also, the clogging of water in the soil could congest the root ball, causing them to rot. Therefore, it is essential to allow the soil to dry up a little to enable the roots to take up enough oxygen.

The type of water best suited for watering rex begonia is also a critical factor to consider. You can use rain, spring, and distilled water for your rex begonia. These have shown superiority over tap water. The reason is that tap water causes undissolved minerals to accumulate in the soil. This occurrence further causes problems to the roots and hence, the entire plant. 

When watering a rex begonia plant, you should only water the soil and never the foliage. Yet, could the leaves at least be misted?

Should I Mist My Rex Begonia?

Misting a healthy rex begonia plant is not ideal. On the contrary, it is usually a common mistake, all in an attempt to keep the plant’s foliage fresh always. Still, let me explain what happens when you mist rex begonia.

First, note that the rex begonia only transports a trace amount of water from the soil to its leaves. Thus, Rex is unlike many other plants with high amounts of chlorophyll in leaves. These chlorophyll are responsible for using water and sunlight to produce starch. Therefore, leaves that have low chlorophyll don’t require much water. As a result, the plant prefers vaporized water to keep them fresh.

This preference accounts for rex begonia requiring a high humid environment with sufficient moisture in the air. So, misting the plant’s leaves is not needed. In the worst-case scenario, misting can cause powdery mildew. 

Powdery mildew is a disease that affects the foliage of rex begonia when moisture is retained on them. 

Therefore, rather than misting, it would be best if you made efforts to increase humidity around the rex begonia plant. This simple action can enable effective growth.

Rex Begonia Propagation

Rex Begonia Care: Everything You Need to Know

Whether you have an eye for ornamental plants or not, the rex begonia has its way of attracting you to itself. This attraction eventually pulls you to get one yourself. So now, how can you propagate a rex begonia plant?

You can propagate rex begonia by seed and asexually from leaf or stem cuttings. The plant has a very tiny seed which it produces at the close of its life cycle. Due to this, it is advantageous to get vibrant and resistant seeds from a commercial nursery with experienced gardeners when propagating by seed. A potting mix is the recommended soil for propagation.

After sowing, a rex begonia seed could take 15-20 days to germinate into full sight. For seeds to germinate effectively, sufficient light is required. Hence, they are not sunk too deep in the soil. Nevertheless, oxygen is required as much as moisture is, so do not saturate the soil with excess moisture.

Propagation by leaf and stem cutting is a little more reliable and less delicate than seeds. When propagating with leaf-cutting, the leaf should be pinned down to the soil to maximize germination points. That said, the soil used here should also be seed-starting and provided with adequate moisture and light.

Here is a good contrast; rex begonia propagated by seed may look nothing like their parent plant. On the other hand, propagation by leaf and especially stem cuttings ensure the cloning of the parent plant. Under suitable conditions, both methods are effective and in no time produce cherished foliage.

Rex Begonia Care Outside

Caring for rex begonia outdoors can be compared to looking after a child in a playground. A common feature in both cases is the undistracted attention required by both. But, you’ll also have to supplement the needs of rex begonia not provided by nature.

When cultivating a rex begonia outside, citing the location is the first and most crucial step. My first mistake was choosing a good vantage point where its beauty was more pronounced, especially to passersby. However, it was more profitable choosing a location that met the basic requirements for growing rex begonia, such as humidity, light, and space.

That said, it would be best if you placed rex begonia where it has access to indirect sunlight, preferably under a medium tree with sparse branches. Placing rex begonia in a basket on a porch is also acceptable, provided it receives sufficient moderate sunlight each day. Also, the plant should be promptly shaded whenever the leaves start appearing crisp, dry, or brown.

Watering rex begonia outdoors calls for consciousness and alertness. Therefore, it is essential to check the moisture content of the soil frequently as evaporation rates could increase at any time. Furthermore, outdoor rex begonia, when healthy, should also not be misted even when humidity is low.

Given the above, you cannot cultivate rex begonia during the winter months. Therefore, it is best to move your plant to a suitable position indoors until after the frost during this period.

Is Rex Begonia Prone to Diseases and Pests?

Rex Begonia Care: Everything You Need to Know

Surprisingly, despite being reasonably demanding to cultivate, rex begonia is not prone to many diseases but to a single pest – mealy bugs. Notwithstanding, you need to be mindful of a few other problems which could occur. They include; leaf blight, powdery mildew, and root rot.

Mealy bugs often infect rex begonia when the air is dry and less humid. They are sap-sucking insects that target the stem and leaves of rex begonia, where they obtain food. When present, it is usually an infestation, i.e., they attack the plant in large numbers.

Whenever there is a cottony mass on leaves and stems, especially in joints, this signifies the presence of mealy bugs. They can be prevented by keeping humidity as high as possible, especially when indoors. A control measure against mealy bugs in rex begonia is spraying the leaves with alcohol.

Powdery mildew results from excess moisture in the soil and on the leaves and foliage of rex begonia. You can identify this occurrence by the appearance of a white powdery substance that covers the leaves and foliage of the plant. Avoiding misting and the spray of fungicide when present is also an excellent way to fight powdery mildew.

rex begonia in itself is a resistant variety from the begonia family. Thus, when you meet proper conditions of growth, a smooth generation is often assured.

Rex Begonia Crispy Leaves

What is food without taste? Indeed, what is a rex begonia without its flamboyant and attractive foliage? Well, that could very much be describing a rex begonia with crispy Leaves. So how does that come about?

Crispy leaves in rex begonia are caused majorly by lack of soil water as well as low humidity. Rex begonia thrives on humidity, meaning; the more moisture available in the air, the more it grows and develops. Still, rex begonia also requires consistent soil moisture, though not soggy or water-logged soil.

Leaves of rex begonia become crispy when the water in the leaves suffers transpiration without being sufficiently replenished. When leaves become crispy, you can restore the plant by misting mildly from a reasonable distance but not too often. It would help if you did this, especially in the morning, to absorb or dry off before night. 

 In a few cases, crispy leaves accompanied by stunted growth come about due to a lack of nutrients in the soil. Recall that rex begonia has shallow roots, which allow it to take nutrients only from the top and sometimes the immediate subsoil. When the plant uses up the nutrients, its leaves begin to grow crispy and brown.

For this reason, rex begonia is not grown on garden soil but in tropical peat soil or potting mix. That said, transplanting rex begonia with crispy leaves to nutrient-rich soil helps revive and restore the leaves.  

How Many Rex Begonia Plants Can I Put In One Pot?

It would be best if you cultivate only one rex begonia plant in a sizable pot. In our discussion thus far, I have established that rex begonia interacts actively with the atmosphere. In addition, it is worthy to note that the plant spreads its foliage lavishly as it grows.

Given this, there could be health risks and a decline in productivity when you crowd rex begonia. However, when growing smaller varieties, they can be grown with other plants having a slim, upright stem. Cultivating rex begonia together in a single pot is also tolerable when grown in an enormous pot.

Bear in mind that when combining Rex with other plants, these plants should have a similar growing requirement like temperature. Also, the plant should not be a rapid-growing plant with vast foliage. The reason is so that it does not outgrow and crowd out the rex begonia.

How Long Does Rex Begonia Live?

Rex begonia is a perennial plant that can live for about 2-3years. During this period, it lavishly produces attractive foliage provided the conditions are right. Before it drops any foliage, it forms a replacement with circinate vernation, which is already visible.

For potted rex begonia, you can aid them to survive harsh months by moving them indoors. To ensure longevity, provide moderate light, water adequately but avoid wetting the foliage and avoid misting.

As rex begonia approaches the end of its lifespan, it produces seeds that can be collected and propagated. Stems can be cut and kept dormant under moist conditions also to be propagated in favorable conditions. This process will ensure that there is always a rex begonia to beautify the surroundings and bring you delight.