Size
Ultimate height
1.5–2.5 metresTime to ultimate height
1–2 yearsUltimate spread
0.5–1 metresGrowing conditions
Moisture
Moist but well–drainedpH
Acid, Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | ||||
|---|---|---|---|---|
| Summer | Red Yellow | Green | ||
| Autumn | Red Yellow | Green | ||
| Winter |
Position
- Full sun
Aspect
South–facing or West–facing or East–facing
Exposure
Sheltered Hardiness
H3Botanical details
- Family
- Asteraceae
- Native to GB / Ireland
- No
- Foliage
- Deciduous
- Habit
- Clump forming
- Genus
Dahlia are tuberous rooted perennials with pinnately divided leaves and showy flowerheads, double in many cultivars, in summer and autumn
- Name status
Accepted
- Horticultural Group
- Cactus dahlias have fully double blooms, the florets are usually pointed, narrow and revolute for 65% or more of their length and either straight or incurving
How to grow
Cultivation
Grow in fertile, humus-rich, well-drained soil, enriched with organic matter and general purpose fertiliser, in full sun. Pinch out growing tips to encourage bushy plants and stake. Water freely in dry periods. Lift and store tubers in autumn to replant or use as a source of cuttings in spring. See dahlia cultivation
Propagation
Propagate by softwood cuttings taken in spring from shoots from stored tubers, or divide the tubers ensuring each division has a viable bud
Suggested planting locations and garden types
- City and courtyard gardens
- Cottage and informal garden
- Flower borders and beds
- Cut flowers
Pruning
Deadhead to prolong flowering. Cut back to near ground level in the autumn, before lifting and storing for the winter
Pests
May be susceptible to aphids, leaf miners, glasshouse red spider mite and slugs; earwigs sometimes damage blooms. Capsid bug and caterpillars are occasional pests
Diseases
May be susceptible to powdery mildews in dry conditions; grey moulds and other fungal rots in wet conditions; fungal rots on stored tubers and a virus that causes stunting, leaf markings and distortion
Get involved
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