Wax begonia Begonia semperflorens-cultorum
Wax begonia (Begonia semperflorens-cultorum) is an annual flowering plant in the Begoniaceae family, native to Garden hybrid group derived from Brazilian Begonia species. It grows 15–35 cm (6–14 in) tall and 20–35 cm (8–14 in) wide, wants part sun to part shade and moderate water, and is hardy to about 4 °C (39 °F). Space plants about 20 cm (8 in) apart.
Plan Wax begonia in your garden →
Free. Draw your beds, then watch it grow through the year in 2D and 3D.
Wax begonia at a glance
| Type | Annual flowering plant |
|---|---|
| Family | Begoniaceae |
| Mature height | 15–35 cm (6–14 in) |
| Mature spread | 20–35 cm (8–14 in) |
| Spacing | 20 cm (8 in) centre to centre |
| Sun | Part sun to part shade, at least 4 h of direct sun a day |
| Water | Moderate; drought tolerance low, waterlogging tolerance none |
| Soil pH | 5.5–7 |
| Cold hardiness | About 4 °C (39 °F) once established (roughly USDA zone 10) |
| Heat stress | Likely above about 32 °C (90 °F) |
| Flowering | about 5–11 weeks after planting, for 17–29 weeks |
| Days to maturity | About 90 days from planting |
| Wind tolerance | None |
| Pollinator value | Low |
| Edible | Not grown as food |
| Native to | Garden hybrid group derived from Brazilian Begonia species |
| Common in gardens of | 🇺🇸 United States, 🇧🇷 Brazil, 🇸🇬 Singapore |
Is Wax begonia toxic?
- People: mildly toxic
- Cats: moderately toxic
- Dogs: moderately toxic
- Parts: all parts, tubers
Insoluble calcium oxalate crystals (ASPCA lists Begonia as toxic to cats, dogs and horses) cause mouth irritation, drooling and vomiting.
If a child or pet may have eaten part of a plant, call a poison centre or vet straight away.
Companion planting: what to grow with Wax begonia
No well-documented helpful pairing. Group it with plants that like part sun to part shade and moderate water.
See Wax begonia in a botanical garden
It grows in these sample gardens, which you can walk through in 3D:
- The Butchart Gardens (120 plants)
- Longwood Gardens (30 plants)
Questions about Wax begonia
- How far apart should I plant Wax begonia?
- About 20 cm (8 in) apart, centre to centre. A mature plant spreads 20–35 cm (8–14 in).
- Does Wax begonia need full sun?
- Part sun to part shade: at least 4 hours of direct sun a day.
- How much water does Wax begonia need?
- Moderate water. Drought tolerance is low and waterlogging tolerance none.
- How cold-hardy is Wax begonia?
- It tolerates about 4 °C (39 °F) once established, roughly USDA zone 10. As an annual it is usually planted out after the last frost.
- When does Wax begonia flower?
- About 5–11 weeks after planting, for 17–29 weeks.
- Is Wax begonia poisonous to cats and dogs?
- For cats it is moderately toxic; for dogs moderately toxic; for people mildly toxic. Insoluble calcium oxalate crystals (ASPCA lists Begonia as toxic to cats, dogs and horses) cause mouth irritation, drooling and vomiting.
- What grows well with Wax begonia?
- There is no well-documented companion pairing for Wax begonia. Group it with plants that like the same sun (part sun to part shade) and water (moderate).
Sources and evidence
Evidence grade C (C: plausible, mixed evidence).
- RHS Plant Finder, Royal Horticultural Society
- ASPCA Toxic and Non-Toxic Plant List, ASPCA
- UF/IFAS Extension tropical and subtropical fruit and landscape publications, University of Florida
- Flora & Fauna Web, National Parks Board, Singapore
Notes and assumptions
- Typical garden-form values; cultivars and local conditions differ.
- Tender perennial grown as an annual outside frost-free zones (perennial in Singapore and similar climates).
Reference values for planning, not horticultural, veterinary or medical advice. Varieties, soils and local climates differ: check with a local nursery or extension service.
Related plants
- Rex begonia Begonia rex
- Polka-dot begonia (spotted begonia) Begonia maculata
- Sunflower Helianthus annuus
- French marigold Tagetes patula
- English lavender Lavandula angustifolia
- Zinnia Zinnia elegans
- Cosmos Cosmos bipinnatus
- Purple coneflower Echinacea purpurea