Martin Fish repots begonias
They’ve come through winter unscathed and now it’s time to repot them
Begonias come in all shapes and sizes – some are grown for their fantastic flowering displays through the summer while others produce really striking foliage. When it comes to foliage begonia, Begonia rexx is perhaps one of the best-known types, although these days it tends to be hybrids that are grown. Their leaves can be very impressive and when grown in the correct conditions they make a showy plant.
To overwinter they need a minimum temperature of 13C (55F) ideally, so in my greenhouse, where I only maintain frost-free conditions, I stand them in the heated propagator with the lid off. This gentle base heat lifts the temperature around the plants to ensure they come through the winter in good condition.
The two types I’m growing are ‘Rocheart’, with its swirling leaves, and ‘Vesuvius’, which, as you’d expect, has hot, fiery foliage. In early summer I intend to take some leaf cuttings but for now I need to get the plants actively growing to make some new foliage. At the moment they’re in small pots, so I’m moving them up into a slightly larger one to encourage new roots. For the compost mix I’m using half John Innes and half multi-purpose compost that drains well, but at the same time retains moisture. I also find it has a bit more weight and is good for using in pots where the foliage can eventually become top heavy.
The begonias will be grown on in the greenhouse bench where they get good light, but I don’t want them in full sun all day as the foliage can scorch. The compost needs to be kept moist and they like a reasonable amount of humidity when in active growth, so on warm days I’ll occasionally mist them over with water. They should soon respond to being re- potted and make new leaves and a good-shaped plant by summer.