Birthday
HydrangeasThis article was prepared with the support of UFL flower delivery. Begonias are among the most popular plants for homes, balconies and gardens. The genus has about 2,000 species and thousands of hybrids. It's named after Michel Bégon, a French governor and patron of botany, and begonias have been cultivated for over 300 years. If your begonia is growing but not flowering, it's probably missing one of the conditions below.
Types of begonia
Begonias are divided into foliage types (rex begonia, iron cross begonia), grown for their patterned leaves and modest flowers, and flowering types — which this article is about:
- Elatior begonia — the most popular pot plant: lavish flowers almost all year, but it lives only 1–2 years.
- Tuberous begonia — large double flowers in summer, with an essential winter rest.
- Wax begonia (semperflorens) — small flowers all season, great for beds and balconies.
- Cane begonia ("angel wing") — bushy, with spotted leaves and drooping flower clusters.
8 reasons a begonia won't flower
1. Not enough light
Flowering begonias need 10–12 hours of bright, indirect light a day: an east or west window, or a south window with midday shade. A grow light helps in winter. In shade the plant stretches and doesn't set buds.
2. Temperature swings and draughts
Ideally 18–22 °C in summer and no lower than 15 °C in winter. Cold glass, an open window or a nearby radiator stress the plant and it drops its buds. Don't move the pot while it's budding and don't water with cold water.
3. Air that's too dry
Begonias come from the humid tropics of South America, Asia and Africa and need 50–60% humidity. Don't mist the leaves — they'll spot. Instead, stand the pot on a tray of wet pebbles (without the base touching the water), place a bowl of water nearby or use a humidifier.
4. Overwatering
Begonia roots rot easily. Water with soft, room-temperature water once the top 1–2 cm of compost is dry, and empty the saucer. Drainage at the bottom of the pot is essential.
5. The wrong feed
Too much nitrogen gives lush leaves but no flowers. Once buds appear, feed every 2 weeks with a flowering-plant fertiliser high in potassium and phosphorus.
6. The wrong pot or old compost
In a large pot a begonia puts its energy into roots first. Choose a pot only 2–3 cm wider than the root ball and a light, slightly acidic mix for begonias or African violets. Repot every spring.
7. No rest period, or an old plant
Tuberous begonias need a winter rest: reduce watering in autumn, cut off dead stems and store the tubers at 10–12 °C until spring. Elatior begonias are exhausted after 1–2 years of heavy flowering — renew them from cuttings.
8. Pests and diseases
Aphids, spider mites, whitefly and powdery mildew weaken the plant. Check the undersides of leaves regularly and treat with an insecticide or fungicide if needed.
How to get your begonia flowering
- Move it to a bright spot out of direct midday sun.
- Keep the temperature steady and away from draughts and radiators.
- Raise humidity with a pebble tray.
- Water only once the top layer has dried.
- Switch to a potassium-phosphorus fertiliser.
- Pinch out leggy stems — new shoots will bring buds.
FAQ
How long does a begonia flower?
Elatior and wax begonias bloom for several months in a row; tuberous begonias from June until autumn.
Why is my begonia dropping buds?
Dry air, overwatering, draughts or moving the pot while it's budding.
Should I prune a begonia?
Yes — remove spent flowers and pinch out leggy shoots to encourage new blooms.
Want a flowering plant without the fuss? Choose a begonia or other potted plants with delivery from UFL.
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Author: Maria Svitlovir
Graduated from Taras Shevchenko National University of Kyiv, Institute of Biology and Medicine (2001). BSc in Biology, MSc in Horticulture. Writes about plants, works at a garden centre selecting and repotting plants, and contributes to plant reference guides.
