Plant in a sunny spot with well-drained soil. Before planting, incorporate some garden compost or well-rotted organic matter into the soil to help retain moisture while maintaining good drainage.
Water regularly during the first growing season until established, particularly during prolonged dry spells. Once settled in, plants are relatively low maintenance, although they will perform best if the soil does not dry out completely for long periods.
Apply a balanced fertiliser in spring to encourage healthy growth and flowering. A mulch of compost or well-rotted manure around the base of the plant will help conserve moisture and improve soil structure.
Remove faded flower spikes as they finish to encourage a second flush of blooms later in the season. In autumn or late winter, cut back old stems to just above ground level before new growth emerges.
Divide congested clumps every few years in spring or autumn to maintain vigour and keep plants flowering freely. Staking is rarely required, but plants growing in rich soil or more shaded positions may benefit from light support.