Description

Dahlia Black Jack is used for depth, drama and texture. The flowers are a very dark red that can read near black in certain light, with a velvety finish that makes the colour feel even deeper. The bloom form is semi cactus, with long, spiky petals that add movement and a sharper silhouette than a standard decorative dahlia. This combination makes it a strong anchor plant in late summer borders, especially in Irish planting where darker tones help define a scheme and stop it looking flat. Irish horticulturists often place Black Jack in estate borders, feature beds and public planting as a contrast point, using the near black colour to make neighbouring yellows, whites, peaches and silvers look brighter. In private gardens it is best positioned against pale walls, fencing or lighter foliage, or used near patios where the velvety petals and spiky form can be appreciated up close. It also cuts well for moody bouquets and autumn arrangements, and regular cutting or deadheading encourages repeat flowering into autumn. Pair it with white cosmos, pale echinacea, silver foliage, ornamental grasses and lighter dahlias for contrast, or combine it with bronzes and oranges for a rich late season palette. Plant after frost risk has passed, in full sun and fertile, free draining soil improved with compost. Keep moisture steady through summer, stake if exposed, feed from bud stage onwards and deadhead regularly to keep buds forming. Lift and store tubers frost free after the first frosts for reliable replanting in Ireland.