Dahlia Dahlia pinnata hybrids
Dahlia (Dahlia pinnata hybrids) is a deciduous perennial flowering plant in the Asteraceae family. It grows 60 cm–1.5 m (24 in–4.9 ft) tall and 50–90 cm (20–35 in) wide, wants full sun and moderate water, and is hardy to about -1 °C (30 °F). Space plants about 60 cm (24 in) apart.
Plan Dahlia in your garden →
Free. Draw your beds, then watch it grow through the year in 2D and 3D.
Dahlia at a glance
| Type | Perennial flowering plant, deciduous |
|---|---|
| Family | Asteraceae |
| Mature height | 60 cm–1.5 m (24 in–4.9 ft) |
| Mature spread | 50–90 cm (20–35 in) |
| Spacing | 60 cm (24 in) centre to centre |
| Sun | Full sun, at least 6 h of direct sun a day |
| Water | Moderate; drought tolerance low, waterlogging tolerance none |
| Cold hardiness | About -1 °C (30 °F) once established (roughly USDA zone 10) |
| Heat stress | Likely above about 32 °C (90 °F) |
| Flowering | from about July for 13–17 weeks (northern hemisphere; later in cold climates, earlier in warm ones) |
| Wind tolerance | Low |
| Pollinator value | Moderate |
| Edible | Not grown as food |
| Common in gardens of | 🇲🇽 Mexico, 🇬🇧 United Kingdom, 🇺🇸 United States, 🇩🇪 Germany, 🇳🇱 Netherlands |
Is Dahlia toxic?
- People: not known to be toxic
- Cats: mildly toxic
- Dogs: mildly toxic
- Parts: leaves, tubers
Can cause mild stomach upset or skin irritation in cats and dogs.
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 Dahlia
No well-documented helpful pairing. Group it with plants that like full sun and moderate water.
See Dahlia in a botanical garden
It grows in these sample gardens, which you can walk through in 3D:
- UC Botanical Garden, Berkeley (6 plants)
- The Butchart Gardens (30 plants)
- Longwood Gardens (12 plants)
- Monet’s gardens at Giverny (70 plants)
Questions about Dahlia
- How far apart should I plant Dahlia?
- About 60 cm (24 in) apart, centre to centre. A mature plant spreads 50–90 cm (20–35 in).
- Does Dahlia need full sun?
- Full sun: at least 6 hours of direct sun a day.
- How much water does Dahlia need?
- Moderate water. Drought tolerance is low and waterlogging tolerance none.
- How cold-hardy is Dahlia?
- It tolerates about -1 °C (30 °F) once established, roughly USDA zone 10.
- When does Dahlia flower?
- From about July for 13–17 weeks (northern hemisphere; later in cold climates, earlier in warm ones).
- Is Dahlia poisonous to cats and dogs?
- For cats it is mildly toxic; for dogs mildly toxic; for people not known to be toxic. Can cause mild stomach upset or skin irritation in cats and dogs.
- What grows well with Dahlia?
- There is no well-documented companion pairing for Dahlia. Group it with plants that like the same sun (full sun) and water (moderate).
Sources and evidence
Evidence grade C (C: plausible, mixed evidence).
- ASPCA Toxic and Non-Toxic Plant List, ASPCA
- FAO Irrigation and Drainage Paper 56 — Crop Evapotranspiration, FAO
- RHS Plant Finder, Royal Horticultural Society
- University extension gardening guides (general), Various land-grant university extensions
Notes and assumptions
- Typical garden-cultivar values; varieties differ.
- Tubers are lifted in frost 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
- Lettuce Lactuca sativa
- Sunflower Helianthus annuus
- French marigold Tagetes patula
- Zinnia Zinnia elegans
- Cosmos Cosmos bipinnatus
- Purple coneflower Echinacea purpurea
- Black-eyed Susan Rudbeckia hirta
- French tarragon Artemisia dracunculus