Begonias are flamboyant, tender perennials used in bedding, pot and hanging basket displays. There are many types of begonia to grow, from popular tuberous begonias, fibrous-rooted types and hanging begonias, which are ideal for hanging baskets. Larger flowered types are often grown as specimen house plants, as are rex begonias, which have impressive foliage.
All begonia foliage is varied and attractive, and the flowers are long lasting.
How to grow begonias
Grow begonias in peat-free, multi-purpose compost in dappled sunshine to partial shade. Tuberous begonias are perfect for growing in pots, while fibrous rooted types are best for bedding displays and hanging begonias are best suited to hanging basket displays. Water regularly and feed weekly with a high potash fertiliser like tomato feed. In autumn, dig up tuberous begonias and store in a cool, frost-free spot for winter. Throw fibrous-rooted and hanging types on the compost heap.
More on growing begonias:
Where to plant begonias
Begonias are ideal for growing in pots and hanging baskets or can go straight into flower borders. Tuberous begonias have fairly brittle stems and heavy flowers, so grow them in a sheltered spot. Flowers will go over very quickly if they’re too hot.
Begonias grow well in sun or shade – avoid south-facing spots as the foliage can burn in direct sunlight. When growing begonias in a greenhouse, shading may be required.
Fibrous rooted begonias can be packed quite tightly into mixed summer displays of other bedding plants.
How to plant begonias
Buy tuberous and fibrous-rooted begonias in March and plant them into individual pots. Ensure you completely cover tubers with compost. Other types can be bought as pot-grown plants or plugs. Grow all types on in a greenhouse and harden off after all risk of frost has passed.
How to care for begonias
Keep plants well watered but allow the soil to dry out between waterings – this is especially important for tuberous begonias, which can rot in waterlogged soil.
Feed tuberous begonias weekly with tomato feed in summer, especially pot-grown plants. Alternatively, add a slow-release fertiliser pellet to the compost when planting. Never feed tuberous begonias into September as plants should be encouraged to slow down for the year. From October, reduce watering and remove flowers so the plants to put energy back into the tuber. Once the foliage has been blackened by frost, life the plants. Remove the compost from each tuber, cut the stem back to about 6cm and store in a dark, cool, frost-free place until March.
Fibrous-rooted and hanging begonias tend to be grown as annuals. Feed weekly in summer and dig them up and compost them when they’ve finished flowering.
How to propagate begonias
Tuberous begonias don’t come true from seed so propagation by cuttings is recommended. In March or April pull new shoots that form on the tubers away with your fingers. Pot them up into individual pots and put them in a heated propagator. Place the propagator in a shaded spot and expect to see signs of growth within four weeks.
Fibrous-rooted begonias can be grown from seed in early spring. Sow seeds onto moist, seed or multi-purpose compost. They need light to germinate so don’t cover them. Place in a propagator with a lid or cover pots with a clear plastic bag or cling film to retain humidity.
Growing begonias: problem solving
Powdery mildew can be a problem for begonias from May – especially for yellow-flowering types. This fungal disease spreads by spores, so good hygiene should reduce the chances of attack. To prevent the problem space plants out well and ventilate greenhouses. Some gardeners spray plants with a systemic fungicide in May to prevent the problem.
Vine weevil can be a problem with pot-grown begonias.
Find out how to prevent begonias and other bedding plants from becoming leggy, in our Quick Tips video:
Begonia varieties to try
- Begonia ‘Inferno’ (pictured) – provides months of bright orange, weather-resistant flowers
- Begonia x tuberhybrida ‘Giant Picotee Mixed’ – tender perennial with ruffled pink, apricot or yellow flowers from July to October. Height 30cm
- Begonia ‘Lou-Anne’ – tender perennial with pendula pale-pink flowers from July to October. Ideal for baskets
- Begonia ‘Moulin Rouge’ – tender perennial. Giant, crimson-red blooms from July to October measuring 15cm in diameter
- Begonia rex – grown for its large silver and green foliage that has a rusty brown underside. Tender so needs to be grown as a house plant. Height 40cm
- Begonia semperflorens – tender perennials grown as annuals. Small plants with fibrous roots ideal for summer bedding displays. Pink and white flowers. Leathery, shiny green leave. Height 15cm