Eryngium × zabelii 'Jos Eijking (PBR)' Position: full sun Soil: moist, well-drained soil Rate of growth: average Flowering period: August to October Flower colour: steely blue Other features: superb foliage Hardiness: fully hardy
1 Salvia nemorosa 'Caradonna’ from the mildly aromatic silvery green leaves to the violet flower spikes with purple stems. Bees love the flowers that stay looking sharp long after the petals fall, thanks to papery bracts that hold their colour. Dead-heading – either little and often or in one go – encourages new flowering side-shoots till October. 'Caradonna’ loves sun; use it as a purple ribbon through late season grasses or, at 18in (45cm), it is the perfect centrepiece for a pot.
Aster 'Little Carlow'.Masses of small, cheerful, violet-blue daisies with bright yellow centres appear from late summer to mid-autumn on soft stems. A pretty aster that has been given the Award of Garden Merit by the Royal Horticultural Society. It loves some shade and will add a splash of colour to a late summer border.