Hardy begonias: cold tolerant species & cultivars

Sarah

For me plants are some of the most exciting living beings, even though they live in slow motion. They have fascinating abilities and just so much potential! That's why I studied organic farming. However, since plants are rather thin on the ground in my city, I often spend time hiking in the nearby mountains at the weekend. In the future I would love to run a farm myself.

Favourite fruit: strawberries and gooseberries
Favourite vegetable: courgettes

Even though the begonia actually likes it warm, there are hardy varieties that can survive our winters. We present two hardy begonias.

hardy begonia plants in bloom — One of the few begonia species that can survive cold winters is the hardy begonia (Begonia grandis) [Photo: Kollawat Somsri/ Shutterstock.com]

In summer, the exotic begonias (Begonia) are beautiful to look at. But if you do not make the effort in the winter and dig them up again or bring the pots indoors, then every spring you will have to start buying new plants again. But with a little luck and propert protection, a few begonia species and varieties survive the winter even in our country.

Contents

Are there any hardy begonias?
Hardy begonia species and varieties
Overwintering begonias

Are there any hardy begonias?

The term “hardy” does not really apply to begonias. They are a genus of plants that have chosen the warm tropics and subtropics as their habitat. Here, frost or snow can be seen from time to time at the top of the mountains but begonias do not go that high up. Very few species can cope with even light frosts. The hardy begonia, for example, is native to the mountainous areas to the west of Beijing, where winter temperatures often fall below 0 °C. The species Begonia panchtharensis, which originates from the Himalayas, can also survive our winters if well protected. There are probably still some species living in the mountain regions of Asia that are unknown to us and could survive the winter in Central Europe. Who knows, perhaps one or two surprises await us in the years and decades to come?

Hardy begonia species and varieties

The hardy begonia is a beautiful perennial for the garden. It is able to transform even shady areas under trees or copses into beautiful places. With a height of 60 centimetres (in exceptional cases even 80 centimetres) it reaches a stately height. After winter, the begonia sprouts against at the end of May, so it is not at the mercy of late frosts. Also the flowers appear late in the year from August but then continue to add beauty to the garden until well into autumn, with their delicate shades of white and pink. The leaves on the other hand are a strong shade of green on the upper side and are streaked with red veins. In red underside of the leaves provides a contrast to this.

The species has several subspecies and varieties:

‘Heron’s Pirouette’: The variety ‘Heron’s Pirouette’ grows to a height of between 60 and 90 cm. It bears large leaves and numerous pink flowers.
‘Sapporo’: this variety has deep pink flowers and can grow up to 80 cm high.
Ssp. evansiana: The very well-known subspecies of hardy begonia has light pink flowers and reaches a height of up to 80 cm.
‘Claret Jug’: This cultivar bears the most vigorous leaf colouration of all hardy begonias and grows up to 70 cm tall.
‘Marie’: The variety ‘Marie’ remains small with a height around 40 cm.
Ssp. grandis: The subspecies grandis is exceedingly vigorous but does not grow taller than 70 cm.
‘Alba’: The variety ‘Alba’ with its pure white flowers is quite special.
Ssp. sinensis: This subspecies of hardy begonia grows only about 30 cm tall. It has smaller leaves but a more upright growth habit. The pink flowers appear from July.
‘Red Undies’: The underside of the leaves of this variety are a particularly intense red.

hardy begonia with pink flowers — Perhaps there are some hardy begonias still to be found, like this specimen in a Nepalese national park [Photo: Yundengogo/ Shutterstock.com]

The species Begonia panchtharensis comes from the Nepalese part of the Himalayan mountains. Their leaves have a totally different shape compared to most begonias. They are deeply indented and grow up to 60 cm long. In fact, they are probably more reminiscent of the leaves of a giant hogweed (Heracleum mantegazzianum) than that of a begonia. It is recognisable as a begonia, however, from July with its delicate pink flowers. The species is considered relatively hardy and can survive frosts down to -9 °C.

Find more great begonia species and varieties for the garden here.

Overwintering begonias

Even the so-called hardy begonias need sufficient frost protection. After all, these species are not really hardy. Winter in Germany, Austria or Switzerland can easily get colder than -10 °C. To ensure that the plants still survive the winter, they should be given a warm coat of brushwood, leaves and mulch. In autumn, the above-ground parts of the plants die and retreat underground. Then it is time to cover the plants thickly. In rough locations, however, even this is often not enough. Then you should dig up the plants after the first light frost and overwinter them in a pot between 3 °C and 10 °C indoors or in the garage.

The hardy begonia forms breeding buds in its leaf axils, so-called bulbils. These often survive the winter even if the mother plant dies. In spring, wherever the bulbils have fallen, young plants then grow. If you want to be sure that the bulblets survive, you should also collect some in autumn and keep them in the refrigerator overwinter. Then in March you can pre-grow the small around bulblets indoors.

For more information on overwintering begonias, see our dedicated article on the subject.