This selection of shrubs is chosen specifically for the poor, thin, acid soils common on the upper parts of the Howth Penninsula. The two we have selected below are at their best this month.
It is hard to imagine a plant more deserving of a place in the early summer garden than cistus, or the sun rose. As tulips lose their shape and the apple blossom goes over, cistus comes into flower and, along with peonies, help to bridge the flowering gap until roses begin in earnest in mid-June. And what flowers they are. Single, flat and saucer-shaped, with five thin petals, they are creased like tissue paper when they first unfold and come in either white or shades of pink, depending on the variety. Each lasts for only one day, but the plant is so covered in buds that you can depend on new ones opening daily over at least a three-week period.
There are 20 or so species of cistus, all of which are evergreen shrubs. They come originally from the Canary Islands and countries bordering the Mediterranean. Cistus ladanifer, the gum cistus, is a generally hardy, upright shrub, growing to 2m by 1.5m (6.5ft by 5ft) if planted in a favoured spot, such as a south-facing wall border. Ladanum, a commercially extracted gum, comes from this species. The shoots are sticky and the imposing leaves are dark green and lance-shaped. The flowers, which measure 10cm (4in) across, have yellow stamens in the centre, surrounded by five distinctive, deep crimson-red blotches, which look like dried blood. The flowers are carried singly at the end of sideshoots in May and June.
Plants named Cistus ladanifer in garden centres and catalogues often turn out to be the similar but better-shaped cultivar, ‘Paladin’ or C. ladanifer var. sulcatus (formerly C. palhinhae). C. ladanifer var. albiflorus, which you may come across in specialist catalogues, is a form without the red spots on its petals.
One of the best forms for the non-specialist to try is Cistus x cyprius. This hardy hybrid of C. ladanifer and C. laurifolius is an excellent garden plant. Its flowersare similar to those of C. ladanifer, but they are carried in groups at the end of shoots. The leaves are bright green and aromatic. In time, this rounded shrub will grow to about 2m by 2m (6.5ft by 6.5ft). Cistus x dansereaui is similar to C. x cyprius, but grows to only about 1m high and across, making it ideal for small garden. It also has slightly smaller flowers. There is a form called ‘Decumbens’, which grows to only 60cm (24in), and also one called, variously, C. x dansereaui ‘Albiflorus’ or ‘Portmeirion’.