The tall hybrid delphiniums are hardy, herbaceous, summer-flowering perennials and favourites for a cottage-garden look. Flower colours are mostly blue, white, and blue-mauve. The flower spikes are carried on long.
Suitable site and soil. Give delphiniums a sunny border with deep, rich soil and shelter from wind. They do not like extremely acid soils and prefer neutral to limy ones.
Cultivation and care. Plant out from autumn to early spring inof three or more. Set strong stakes in mid-spring. After flowering, cut back to a strong to produce a second blooming. Cut to ground level in autumn.
Propagation. Take 10cm – 4inof new spring growth as close to the as possible and insert in 50 – 50 mixture of peat and sand in a cold frame. Transplant in late spring to a nursery bed and plant in permanent positions in autumn. Sow as soon as possible, as it does not keep.
Recommended varieties. D. elatum has l-1.5m – 3-5ft flower spikes and most garden varieties derive from it including ‘Belladonna Improved’, blue, white and pink (height 90cm – 3ft); ‘Dwarf Blue Heaven’, sky-blue, single, no staking; ‘Pacific Giant Mixed’ and other ‘Pacific’ strains, blue, mauve, chocolate, white, semi-double and single flowers; ‘Butterball’, cream; ‘Moonbeam’, white, ‘Loch Leven’, sky-blue.
Pests and diseases. Slugs and snails may be a problem. Various rots and powderyoccur on plants in poor soils or extremes of wetness or dryness.
CREATING A COTTAGE GARDEN BORDER
are perfect flowers for the cottage garden look. As they are so tall, plant them at the back and fill the foreground with , pinks, peonies and other old-fashioned favourites.