CISTUS CRISPUS.--Portugal, 1656. This is a distinct species, with
curled leaves, and large reddish-purple flowers. It is a valuable
ornamental shrub, but, like the others, suffers from the effects of
C. LADANIFERUS.--Gum Cistus. Spain, 1629. A pretty but rather tender
shrub, growing in favourable situations to about 4 feet in height. It
has lanceolate leaves that are glutinous above, and thickly covered
with a whitish tomentum on the under sides, and large and showy vhite
flowers with a conspicuous purple blotch at the base of each petal.
Unless in southern and western England, but particularly on the
sea-coast, this handsome Portuguese shrub is not to be depended on, in
so far as hardihood is concerned.
C. LAURIFOLIUS.--Laurel-leaved Cistus. Spain, 1731. This is the
hardiest species in cultivation, but, like the latter, is favourable to
the milder parts of these islands, and especially maritime districts.
Frequently it rises to 7 feet in height, and is then an object of great
beauty, the large yellowish-white flowers showing well above the deep
green Laurel-like leaves.
C. MONSPELIENSIS (South of Europe, 1656), and its variety C.
monspeliensis florentinus, the former with white, and the latter with
white and yellow flowers, are fairly hardy in the milder parts of
Britain, but cannot be recommended for general planting.
C. PURPUREUS.--Purple-flowered Cistas. In this species, which may rank
next to the latter in point of hardihood, the flowers are of a deep
reddish-purple, and with a darker blotch at the base of each petal.
C. SALVIFOLIUS is of loose and rather untidy growth, with rugose leaves
and white flowers. It is very variable in character, and the form
generally cultivated grows about 4 feet high, and has ovate-lanceolate,
almost glabrous leaves.
Other species that are occasionally to be found in collections are C.
creticus, with yellow and purple flowers; C. hirsutus, white with
yellow blotches at the base of the petals; and C. Clusii, with very
large pure-white flowers. All the species of Gum Cistus, or Rock Rose
as they are very appropriately named, will be found to succeed best
when planted in exalted positions, and among light, though rich, strong
soil. They are easy of propagation.
Other C Tree Species