dahlia 'Stadt Spremberg'

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. Cut down once damaged by frost. Tubers may survive outdoors in mild areas with a good covering of mulch. Otherwise lift and store tubers in autumn to replant, or use as a source of cuttings, in spring. See dahlia cultivation

Deadhead to prolong flowering

Propagate by softwood cuttings taken in spring from shoots from stored tubers, or divide the tubers ensuring each division has a viable bud

Aphids, leaf miners, glasshouse red spider mite and slugs are common pests. Earwigs sometimes damage blooms. Capsid bug and caterpillars are occasional pests

Powdery mildews can be damaging in dry conditions. In wet weather grey moulds and other fungal rots can be a problem. Fungal rots can also damage stored tubers. A virus may cause stunting, leaf markings and distortion