Mystic Spires Blue sends up spires of dark blue-purple flowers all summer long and can make a real impact in borders or in pots on terraces. Dead head spent flowers to gain more as your reward. Plant in full sun for a dazzling display of upright spires on a well branched plant. As with all Salvia, Mystic Spires a banquet for bees, butterflies and other pollinators. This is a tender perennial, so to ensure survival for following years take cuttings, they will root easily. In sheltered spots you can try over-wintering them in situ’ with an adequate application of cossetting mulch.
The tall magnificent spikes of double flowers of Delphiniums have long been prized by gardeners and flower arrangers alike. Pacific Giants come in a range of colours from pale blues, pinks, white and lilac through to the more dramatic deep blues, purples. They add height and structure to herbaceous borders often topping out at 150cm or more and staking is useful. Plant in fertile, well-drained soil. They benefit from a winter mulch. Remove spent spikes to encourage further flowering. Harmful if eaten and can be an irritant to the skin.
Height 150cm and spread 75cm.
An Australian native plant, largely grown for its attractive silvery, velvety, ribbed, heart-shaped leaves. And it will needs plenty of pinching out to give it a bushier appearance. Pretty mauve-blue flowers are borne on small spires that appear in summer. Enjoys a sunny position in the garden on well-drained soil but can also be used to provide interesting foliage under garden trees where other plants aren’t willing to perform.
A stunning plant that is prized for its metallic look to the blue-green fleshy leaves. Cerinthe major purpurascens commonly called Honeywort, prefers humus rich, well-drained soil with some sun or part shade. Hardy down to -5°C. Pinch out young plants for a bigger display of the beautiful nodding, tubular blue-purple flowers that are surrounded by blue-purple bracts . It’s an annual that can be persuaded to act in a perennial way if it likes its conditions, otherwise just collect the seed and sow the following year after frosts have passed.
Height 60cm and spread 60cm.
This Agapanthus inapertus has dark blue-black pendulous flowers in high summer. When planted en masse they are highly dramatic, but also work well as a specimen in pots or containers. Dark blue, almost black buds open to reveal violet-purple flowers that mark this deciduous agapanthus. Thick stout stems rise above the green strappy leaves. A. inapertus is slightly hardier than evergreen cultivars. Position in full sun, on well-drained soil. Will tolerate some winter wetness, but position in full sun, on well-drained soil with some grit incorporated into it.