The Bounty of Begonias

What if I told you that begonias are much more than meets the eye? Horticulturist Tyler Howard shares his favourites and how to grow them.

Begonias have so much more to offer than the classic fleshy flowerer —often sold as potted colour — that we’re all used to. There are thousands of cultivars of begonias on offer, and they are well worth growing.For me, I’m fond of the rhizomatous begonias, which have thick fleshy stems that trail along the pot surface, such as Rex begonias, as well as cane and thick-stemmed begonias. They often have large, lush, and patterned foliage, but some are barely the size of a 50-cent piece, and equally as fascinating. 



Coming from the humid rainforests of Africa, Southern Asia, and Southern and Central America, these plants have adapted to grow with shallow roots in warm climates, but many do well outdoors in Sydney. Just be wary of frost and boggy areas if you plant them in the ground.

How to grow cane and rhizomatous begonias

In pots, canes and rhizomatous begonias need a freely draining growing mix with regular light feeding for best results. The old adage of weakly, weekly, rings true for growing great begonias, especially the rhizomatous varieties. 



You can apply diluted fertiliser more frequently, like Neutrog’s Strike Back for Orchids, applied fortnightly at one-quarter the recommended rate. By and large, begonias are going to need a warm, partly shaded position in the shade house or under some trees.



There are hundreds of rhizomatous cultivars, especially in the Rex group. These excellent indoor and garden specimens need bright indirect (or dappled) light, and will require a free draining mix such as a blend of orchid compost and premium potting mix. For levels of light, think of planting or placing under a tree or in a shade house covered in 30- to 70-percent grade shade cloth. As a rule of thumb, I always recommend keeping them in pots.



Canes will thrive both in the garden and in pots, as they are quite resilient. In the garden, enrich the soil soil with plenty of organic matter and some grit or sand to improve drainage. In pots, remember to feed during the warmer months and repot them in late spring.



My general growing media ‘recipe' for rhizomatous begonias is one-part horticultural pumice (or grit), one-part orchid mix, three-parts premium potting mix. Alternatively, you can substitute pumice for coarse perlite. This blend ensures for a freely draining potting media, whilst retaining nutrients and water without becoming boggy. Be mindful not to over-water your begonias! Rhizomatous begonias have evolved to store some water in their thick stems, so let them partially dry out before their next watering.

 

Pests

Keep an eye out for slugs and snails, as well as some caterpillars. Slug pellets and Yates Success Ultra will be your ally!

Tyler’s Top 5

1. Begonia ‘Tiger Paws’ miniature rhizomatous with unique patterning.





2. Begonia ‘Xanadu’ large, neon-green leaves with distinct veins.





3. Begonia luxurians large cane begonia with thick stems, foliage similar to rhapis palms.





4. Begonia ‘Sophie Cecile’ perfect cane begonia for gardens and pots in Sydney.





5. Begonia ‘Escargot’ rhizomatous begonia with silvery spiral foliage.