How to grow begonias

The begonia family produces beautiful and varied flowers and leaves.

Begonias are one of the most varied and attractive plant families for both indoor and outdoor planting. In warm southern climates, they can grow outdoors year round, and in cooler climates they make great annual bedding plants and spectacular indoor plants. All begonias like warmth, humidity, good air circulation, and careful attention to their water needs. To decide which of the subgroups of the begonia family best fit your needs, consider the list below.


Tuberous begonias are one of the most dramatic and familiar members of the begonia family. Unlike many flowers, they don't need a lot of light. They will flourish in bright indirect indoors or light shade outside.

Tuberous begonias like warm but not hot soil, and can't take direct sun. They come in upright and trailing forms and produce incredible flowers in a wide range of colors through white and pink to orange, salmon, scarlet and intense reds. There are also mixed color, ruffled, frilled and picotee varieties which are incredibly beautifully and free blooming. One variety, the Non-Stop, easily lives up to its name, producing quantities of flowers for a long time.

Generally they are grown as potted plants, both indoors and out. To start them, purchase and plant a tuber which looks like a small rather squashed potato but contains the potential for a large, multi-flowered plant. Make sure the tuber is firm and doesn't have any soft spots. Notice the cup or indentation on one side. This is the top from which the plant will grow, be sure to plant with it up You may notice some eyes or shoots around the indentation. These are the beginnings of the plant, and are not a problem, for they show that the bulb is healthy and eager to grow. Try not to break or harm them, and plant the tuber with the indentation up, 2-3 inches down in a loose, well-drained potting mix with plenty of peat to hold the moisture the plant needs. Keep the soil evenly moist and don't let water stand in the pot. Once the begonias start blooming, fertilize every two weeks to keep them blooming freely.

If you're growing them outdoors, protect from slugs and snails. High humidity and cool weather can cause powdery mildew on leaves- make sure they have good air circulation and spray with fungicide if mildew appears. When they go dormant in autumn, allow them to dry until foliage withers, lift the tubers and store them in vermiculite, misting occasionally if they appear to be shriveling. Plant again next year. Tuberous begonias are one of the easiest and most spectacular flowering plants you can grow.


This is the type of begonia you frequently see in the garden. The plants are small and grow in clumps. Their flowers are not as large as the tuberous begonia but wax begonias are easy to grow, cheerful and free blooming. Their profuse, small lobed flowers are usually red, pink or white but some bi-colors have been developed. They are called wax begonias because of their shiny green or bronze leaves and are particularly popular in the flower garden as a massed bedding or border plant.

Start with nursery plants rather than seed. Look for plants that are well established with strong root systems and which show healthy new growth and flower buds. The plants are somewhat fragile. Their leaves and stems break easily but if the broken leaves and stems are planted, they will root and grow. Their soil needs to be slightly dry in order to prevent rot. Although they can live for more than one season, most gardeners prefer to treat them as annuals and plant anew each spring.


The Rex Begonia is also called the rhizomatous begonia because it grows from a rhizome, a thickening of the stem. Rex Begonias are usually grown indoors. They are usually between 6 and 18 inches tall and are usually grown for their stunningly spectacular foliage rather than their flowers. Begonias Rex leaf colors include green, pink, red, silver, purple and gray in an amazing variety of patterns. The leaves are not only highly colored, but they have an exquisitely lustrous, luminous or even metallic look that is difficult to convey in words.

They are easy to propagate from cuttings and will even grow new plants from a leaf if the soil and leaf cutting are kept properly moist. They like temperatures between 55 and 75 degrees. Bright indirect light, high humidity- spray air, not leaves, allow to dry almost completely between thorough They love bright indirect light and good humidity. Spray the air around them, not their leaves. Let the soil dry moderately between watering and never let them stand in water. Keep them healthy by removing spent leaves. Like all begonias they are vulnerable to rot and mildew. You can use a systemic fungicide for powdery mildew, but be careful to follow instructions precisely.

In spring and summer, fertilize Rex Begonias with a balanced formula or timed-release fertilizer. Do not fertilize in fall or winter. Plants may go dormant in winter light. While they are dormant, water them sparingly and they will revive when the days grow longer in spring. If the rhizome grows too big, prune it and use it to start a new plant.

Another old-fashioned relative of the Rex Begonia is the beefsteak or pond lily variety. Don't confuse this with the Omaha Beefsteak Rex Begonia. Pond lily may be a better name for it, although it is a semi-upright variety. It has five inch wide round green leaves which are red on the underside. It produces upright sprays of charming small pinkish white flowers, and if it's in an environment it likes, it will spread and grow amazingly. It is said to like artificial light and will even thrive under florescent lights. It's clearly a plant from tropical forest under-story. It has periodically been very popular, but is currently hard to find in nurseries. However, it is very easy to propagate, and you may be able to find one through a gardening web-site or on E-Bay.


This giant of the begonia family is usually grown indoors. The Cane Begonia can grow to ten feet tall, so make sure you have plenty of room if you choose this one. The most popular variety is the Angel Wing Upright, a hybrid indoor plant that comes in a number of beautiful varieties of leaf, and has small attractive flowers in hanging clusters, usually pink. It likes the same kind of care as its relatives. Keep its feet dry and the air moist, use a potting mix with plenty of peat, fertilize regularly, and stake it up when it starts to get tall. Your Cane Begonia will probably only grow to be two or three feet tall, but you never know.

To learn more about begonias, and to see pictures of the leaves and blossoms that delight begonia fanciers, go to the Internet, the garden store, or the library. You won't be disappointed.

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