564 
THE GARDENERS' MAGAZINE. 
Juw 26, 1913. 
I THE ROCK ROSES, OR GUM | 
I CISTUSES. I 
The cistuses, when in full beauty from 
May to July, form one of our most showy 
families of shrubs. Being natives of South 
Europe, particularly in what is known as 
the Mediterranean region. North Africa, 
and the Canary Islands, warm and shel¬ 
tered spots should be chosen for their cul¬ 
tivation. In the favourable climate of the 
south and west the rock roses, to use a 
familiar expression, “ grow like weeds.” 
The mild winters of the last few years 
have been very favourable for their growth 
in most gardens, but oocasionaJly a more 
In oold localities it is advisable to plant 
the rock roses at the foot of sunny south 
walls. Sunny banks of sandy soil may be 
effectively clothed with cistus in company 
with, if thought desirable, the double furze 
and the more vigorous-growing helianthe- 
mums. The top of the rock garden, where 
the position is the hottest and well drained, 
and possibly consisting largely of stones, 
will grow rock roses. Wherever planted, 
the soil must be well drained, an excess of 
water at the roots of cist uses in winter 
being (fatal; the position also must be 
time to time it becomes necessary to renlatm 
old and straggly plants with young st^ 
A pot of cuttings, at any rate, of the nus. 
tender sorts, should be inserted each 
lest there should he losses through swen 
frosts. This will entail very little tronkh 
and, if not required, they may be dk’ 
carded in spring. 
In Sweet’s Cistineae, published from 1825 
to 1830, fifty-two species and varieties ut 
described. The “ Kew Hand-list” enc* 
merates twenty-five species and varietw*, 
which may be taken as a guide to the nnai. 
ber now in cultivation. Their ne«r^t 
allies are the helian them urns. The two 
genera are fairly easy to distinguish at i 
glance, the cistus in most instances being 
much more vigorous in growth. BoUni^ 
ally the great difference is in the wed 
vessels, the hdianthemums being three^ 
celled and the cistuses five-celled or more. 
The yellow-flowered Helianthenmm forroo. 
CISTUS LADANIFERUS. 
Flowers white and of large size. 
severe winter than usual is experienced, 
killing a good many plants outright, unless 
protected or growing in warm, sheltered 
spots. 
There are, however, varying degrees of 
hardiness among the cistuses, for whereas 
many species were killed outright at Kew 
during the severe frost of January and 
February, 1895, C. laurifolius was un¬ 
harmed. The fact that some of the rock 
roses are just on the borderline of hardi¬ 
ness should not prevent cultivators plant¬ 
ing them, for cuttings may (be rooted in a 
cold frame towards tne end of the summer, 
and these will soon replace losses occa¬ 
sioned by a more than usually severe prin¬ 
ter. The flowers only last a day each, but 
any drawbacks in this direction are more 
than counterbalanced by the quantities of 
flowers -each plant produces from day to 
day. 
sunny. Few plants repay more fully any 
little extra trouble in caring for their wel¬ 
fare than do the rock roses or gum cistus, 
either in the selection of a position for 
planting, the provision of soil, or protection 
from severe frosts in winter with mats, 
bracken, or spruce and yew branches. 
Seeds and cuttings form ready means of 
propagation. The seeds may be sown as 
soon as ripe, or in spring. Cuttings root 
freely in a oold frame towards the end of 
the summer. Light, sandy soil should be 
used in filling the cutting pots, or, if 
large numibers of cuttings are to be 
inserted, a well-drained bed of sandy soil 
should be made up in the frame. Cistus 
being most difiScult plants to transplant 
successfully, even in a small state, from the 
nursery b^s to their permanent quarters, 
they should be cultivated in pots till large 
enough to plant out permanently. From 
sum is sometimes grown as 
sus, but, strictly speaking, there 
yellow-flowered cistus. 
C. albidus. 
The specific name refers to the 
which are a hoary-white colour, ^ 
covered with a dense pubescence. 
rose-coloured flowers are ^ centrf' 
or rather more across, with a 
It forms a large, compact 
to five feet high. The leaves are 
uniting at the base, and 
stem. A native of Corsica, 
France, Portugal, and Italy. 
C. corbariensis. 
This is a natural hybrid, 
wild in the mountains of Sou the q 
and Spain. The reputed pareii , 
populifolius and C. salvifohi^; jjjs 
free-growing rock rose, spreading 
