Begonia
Like the closely related houseplant foliage Begonia template in this KB, this genus is not frost-hardy — the tubers must be lifted and stored dry over winter in all but the mildest UK gardens, the same principle as Gladiolus and this KB's other half-hardy summer bulbs.
Care
Flowers well in shade where many summer bedding plants struggle, making this genus a useful choice for a shady patio or border; avoid intense midday sun, which scorches the flowers and leaves.
Regular watering, especially in pots and baskets; avoid wetting the flowers directly, which can encourage botrytis.
Fertile, free-draining compost or soil, rich in organic matter.
Deadhead spent flowers regularly; pinch out growing tips on young plants to encourage bushier growth.
A high-potash liquid feed every two weeks from the time the plant is growing strongly until flowering ends. Stop as the leaves begin to yellow in autumn — the tuber is going dormant and further feeding only risks rot in store.
Cut a large tuber into pieces in spring, each with a visible shoot, and let the cut surfaces dry for a day before potting to stop them rotting. Basal cuttings from shoots on a started tuber are the alternative.
Month by month
Months change with the climate: in southern Italy tomatoes go out two months earlier than in England.
- MarchStart tubers into growth indoors in a warm, bright spot, concave side up, ready for planting out after the frost risk has passed. how ›
- JunePlant out once the risk of frost has passed; this genus is not frost-hardy. how ›
- OctoberLift tubers before the first hard frost, dry off, and store somewhere cool, dry and frost-free over winter for replanting next year. how ›
Months based on climate: UK. Your choice stays on this device.
- MarchStart tubers into growth indoors in a warm, bright spot, concave side up, ready for planting out after the frost risk has passed. how ›
- MayPlant out once the risk of frost has passed; this genus is not frost-hardy. how ›
- OctoberLift tubers before the first hard frost, dry off, and store somewhere cool, dry and frost-free over winter for replanting next year. how ›
Months based on climate: Northern Italy. Your choice stays on this device.
- FebruaryStart tubers into growth indoors in a warm, bright spot, concave side up, ready for planting out after the frost risk has passed. how ›
- MayPlant out once the risk of frost has passed; this genus is not frost-hardy. how ›
- NovemberLift tubers before the first hard frost, dry off, and store somewhere cool, dry and frost-free over winter for replanting next year. how ›
Months based on climate: Central Italy. Your choice stays on this device.
- FebruaryStart tubers into growth indoors in a warm, bright spot, concave side up, ready for planting out after the frost risk has passed. how ›
- AprilPlant out once the risk of frost has passed; this genus is not frost-hardy. how ›
- NovemberLift tubers before the first hard frost, dry off, and store somewhere cool, dry and frost-free over winter for replanting next year. how ›
Months based on climate: Southern Italy and islands. Your choice stays on this device.
Common problems
How to spot it. Soft, mushy tubers when lifted or checked.
What to do. Not frost-hardy in the UK — lift before the first hard frost, dry off thoroughly before storing, and keep somewhere cool, dry and frost-free rather than leaving in the ground.
How to spot it. Fuzzy grey growth on flowers, especially in wet weather.
What to do. Avoid overhead watering that wets the flowers directly; deadhead affected blooms promptly and improve air circulation.
How to spot it. Bleached or browned patches, especially at midday.
What to do. This genus prefers part shade — move containers or choose a shadier spot for border plantings if scorch appears.
Questions
Begonia: is it hardy?
H2: Tender. It survives down to 1 °C.
Can it grow in a pot?
Extremely popular for pots and hanging baskets, particularly trailing types, precisely because it flowers so well in shadier spots than most summer bedding.
Begonia: when do you prune it?
Deadhead spent flowers regularly; pinch out growing tips on young plants to encourage bushier growth.
Begonia: when does it flower?
In the climate of UK it flowers in June–September.
When do you feed it?
A high-potash liquid feed every two weeks from the time the plant is growing strongly until flowering ends. Stop as the leaves begin to yellow in autumn — the tuber is going dormant and further feeding only risks rot in store. Feeding months, UK: May–August.