I grow Rex Begonias on my window sills, on stands, tables, and in my breezeway. At one time they were thought to be strictly for the greenhouse hobbyist. Such is not the case anymore!
Basic Cultural House Plants
Today anyone can have the basic cultural know-how to grow these most luxuriant and beautiful of house plants.
Rex begonias can be grown practically anywhere in the house where there is good light and some sun.
Extra Special Catering
Surprisingly enough, most rexes have no need for extra special catering, such as the Wardian case, as is believed by many people. By nature, these plants want and demand humidity, constant moisture, and soil rich in leaf mold.
The requisite leaf mold is to be found in any woodland, regardless of where one may live. The deeper it is around the rocks and stumps, in old swamps, and by ponds and streams, the lusher it is in the required nutrients of rexes.
Woodland Materials
This material, as it is taken from the woodlands, needs to be finely sifted to remove all fibrous roots, unrotted leaves, sticks, and stones. That which remains is soft, black, and velvety to the touch, the basis for the potting medium.
To four parts of leaf mold, add one part of very old finely sifted cow manure, and one part of sifted sand {not sea sand!) and a handful of charcoal. A handful of bone meals is beneficial.
Mix Ingredients Together
All these ingredients must be thoroughly mixed together and the hand-over-hand method proves for me to be the best and safest, for the hands will detect any coarse materials that might have escaped the sifting.
Get the “feel” that the mixture is uniform. After mixing these ingredients, moisten thoroughly so that all of the medium is damp, but not wet. Now the potting process is really ready to begin.
Dry Rex Begonia
At no time should a rex begonia be allowed to become dry. These begonias demand moisture from the soil at the top of the pot to that at the bottom. At no time should the mixture be drippy wet.
Do not allow the pots to sit in unused water for any length of time, for such will cause root rot. Water thoroughly each time {never just the topsoil). Water again when the soil at the top is slightly crumbly to the touch.
The water used should be slightly tepid so that the tender root system does not become shocked and chilled by cold temperatures such as would come from the ordinary faucet, especially in winter.
Watering in Day Time
The one thing I learned when I first had rexes was that they resent cold, wet feet, and remembering that, I advise that they be watered in the daytime rather than at night, especially during the colder months.
Daytime temperatures usually dry off excess moisture and warm up the soil, thus creating warm evaporation of moisture up around the leaves. Yet, if a rex is dry, it should be watered regardless of the time of the day.
Plants watered at night are mac susceptible to Botrytis blight, and if the weather is cool, be sure the plant is well drained and not left standing in water overnight.
Watering from the top causes no injury and it is quicker than placing the pots in water to soak up the moisture.
If a plant is not receiving thorough saturation of the soil, it may show signs of dryness by a lack of growth and eventual drooping and dropping of the leavth es.
Humidity
Humidity is definitely required by rexes at all times. In fact, all begonias need it. Humidity needs for house plants can be easily provided.
During the summertime, the windows are open and moisture in the air is provided in a natural way.
Humidity: Spraying With A Fine Mist
Even then, during the day when there is hot, drying air stirring, humidity can be given by spraying with a fine mist of water or setting the pots on moist pebbles, sand, or vermiculite.
If one sprays the leaves, care should be taken to keep the plants out of direct sunlight until the moisture has dried. In the winter I supply the humidity by my cooking, washing dishes, and having a bubbling teakettle on my stove all through the day.
Rexes: Fresh Air
Rexes require fresh air as much as people. If they are on the window sill, it is best not to have that window open at the bottom, because the winds and hot air of summer will take moisture out of the leaves and cause browning.
In the winter the air is too chill. Open the window at the top, or allow fresh air to come from another window, thus coming to the plants indirectly.
Bright light and some sun are needed by all rexes at all times to help keep the leaf colors bright. The sun (and fresh air) helps to prevent fungus problems.
Many varieties can gracefully accept the early to the mid-morning sun, and the late afternoon sun in summer, and in winter, here in New England, I find many varieties will accept, and be most happy, in the full winter sun.
(Especially the darker-toned ones, such as ‘King Edward.’) Some of the silvery-toned ones are likely to burn (`Can-Can’), but if given the mid-morning sun, they will respond with a lustrous sheen. The sun does much in deepening the color tones in rex leaves.
Propagation
Rexes can be propagated by various methods. The leaves may be rooted in water or in a mixture of peatmoss and sand.
The rooting medium must be just nicely moist, and the leaves must have a high percentage of humidity while they are first rooting. The plantlets come up in much the same way as do African violets.
First Potting
For the first potting I prefer to use pure leaf mold and two or 2 1/2-inch pots. I prefer clay pots, though other growers praise plastic pots.
After potting, the young plants are watered thoroughly, allowed to drain well, and then set back into shady quarters for a few days so that they will have a chance to start new growth.
Young Plants
Young plants will thrive if the small pots are grouped together and snuggled into moist leaf mold or peat moss.
Experienced rex begonia growers often propagate from wedges of the leaves. You’ll need a sharp paring knife and a pair of keen-edged shears.
The knife is for cutting the leaves from the plant, and cutting away the leaf stem about one-fourth to one-half inch from the sinus, for it is from the sinus that the rootlets of the new plants grow.
Cut Excess Leaf
With the shears, the wedges are shapedó meaning to cut away the excess leaf.
The wedges need to be 3” inches high at the most. Some people make them triangular, some apple-shaped, but the shape of the wedge has no bearing on its fruitfulness of it.
(I once presumed it did!)
When the wedges are shaped, usually the cut stem and sinus are dipped into a hormone powder, then carefully inserted into the rooting medium to just above the sinus, sprayed in gently but thoroughly with tepid water to settle the medium.
At no time should the medium become dry. Put the tray of wedges where it will receive uniform warmth, night and day, but no direct sun.
Rooting Process
The rooting process is usually quicker if they are kept uncovered, especially in the summer when there are usually spells of very humid weather.
Wedges left uncovered are much less likely to rot before roots have a chance to form.
Leaves used for propagation, and especially for wedges, must be strong and healthy. If one wishes to lay a rex leaf on any rooting medium, the best results are obtained by thoroughly moistening the medium first, and draining off any excess moisture.
Hormone Powder For Treating Cuts
Fine cuts may be made in the large veins on the back of a rex leaf, the cuts treated with hormone powder, and the leaf laid carefully and smoothly on the rooting medium. It is then pinned down carefully (I use hairpins) so as not to penetrate the cut veins.
Leaves rooted in water should be potted as soon as the roots are an inch long.
I’m afraid I like ALL rex begonias, but my favorites are the colorful ones that have personality plus.
These include;
- Merry Christmas
- Fireflush
- Crimson Glory
- Baby Rainbow
- Lorraine Closson
- Ranee
- Redwing
- Mt. Haze
I am most fond of the following;
- Perle de Paris
- Curly Silver Sweet
- Fairy
- Peace
- Can-Can
- Dew Drop
- Inimitable
One of my all-time favorites is ‘King Edward,’ which, in my opinion, will grow anywhere, anytime, under any and all conditions. It has handsome, satiny, dark leaves spotted red.
Yes, I am a rex begonia hobbyist, the addict could be the word, for I enjoy them to the utmost. The more I have the more I want, and so it will be with you!
44659 by V. I. Withee