The trend over the last several years in outdoor gardens is to use more plants with interesting, colourful foliage. Bloom is less important than the interest created by the plants’ foliage itself.
In our indoor gardens, we can easily be in tune with this trend as many homes do not have adequate light levels to allow us to grow many blooming plants. Even in sunrooms, with the short days of winter and cooler temperatures, many blooming plants take a break during the winter and will only resume blooming when the longer days of spring arrive.
Some of the most interesting foliage plants that can be grown indoors are the so-called rex begonias. These lovely foliage plants are grown for their colourful, textured foliage — the leaves often have unique bumpy, hairy, or ridged surfaces.
Leaf texture makes these plants very dramatic in the interior landscape, but the leaves also often have unusual markings. They are usually streaked, splashed or veined with at least one contrasting colour.
Leaf colours can include silver, pink, purple, cream, green, burgundy, and red; most rex begonia foliage has some combination of these colours. The leaves are usually lobed or have a maple leaf-like shape, while leaf edges can be serrated or smooth.
Although some named varieties are available in garden centres, many plants are sold without having their variety name given. ‘Merry Christmas’, a red and green variety and ‘Fireworks’, whose leaves have silvery-green, black and purple markings are just two spectacular varieties.
Another rex begonia variety has unique spiral-shaped leaves and is aptly named ‘Escargot’ because the leaves are appear snail-like. There is even one that has a distinctive, deep burgundy iron cross on its dark green, pebbled leaves.
Most rex begonias are less that 30 centimetres tall although a large, mature specimen planted in a large pot can be 35 cm tall and just as wide. Displayed on a plant stand, such a specimen is stunning indeed.
Tall flower spikes are produced by rex begonias, and small white or pale pink flowers appear at the tops of the stems. Some people cut off these flower stems as they develop while other people think the dainty flower add even more charm to the plants’ appearance.
Rex begonias require a bit of care and are ‘moderate’ in terms of their difficulty to grow. They have definite moisture, humidity, and light requirements if they are to perform well.
Rex begonias like high humidity, so this is one plant that you may want to place on a pebble tray — a saucer full of pebbles on which the pot sits so that the water in the saucer adds to the humidity around the plant while the pebbles hold the pot above the water. If the humidity is too low, the leaves may become dry and brittle.
Rex begonias should not be misted to increase humidity as the water will almost certainly mark the leaves. The soil should be porous with excellent drainage — a potting mix similar to that used for African violets.
These plants grow from rhizomes that are just below the soil surface. Rex begonias should always be grown in shallow pots because they are shallow rooted and using too large or deep a pot will lead to rot of the stems or even the rhizome itself.
Although the planting medium should be kept moderately moist, it doesn’t hurt to let the soil surface dry out between waterings. Add a soluble fertilizer to the water every two weeks in the summer and once a month in the wintertime.
Rex begonias can be propagated by leaf cuttings. Simply insert the stem of the leaf into a soilless mix and enclose the pot in a plastic bag to keep in the moisture. Tiny plantlets will form around the stem in about a month.
If you want to obtain a large number of new plants, you can cut leaves across the veins and insert the cut leaf edges into the planting medium. A tiny plantlet will develop at each vein.
Dwarf varieties are used in terrariums where the plants are right at home in such a high humidity environment. Rex begonias are also used in baskets with other plants as a grouping of plants creates its own humidity.
Wherever you use a rex begonia in your indoor landscape, you will enjoy its dramatic colour and texture. Such unique foliage plants are just what the interior landscape needs during the dreary winter months.
Albert Parsons is a consultant for garden design and landscaping who lives in Minnedosa.