HEDYSARUM HELIANTHEMUM 611 



a few years, we find it a good plan to peg down the branches ; this causes 

 them to break into new growth at the base. The magenta shade in the 

 flower is objectionable to some people, but the shrub is useful in being 

 late flowering and showy. 



HELIANTHEMUM. SUN ROSE. CISTACE,E. 



Only a small proportion of the total number of species of sun roses 

 are hardy, and of these, three shrubby or sub-shrubby ones, and another 

 of only annual duration, occur in Britain. Besides them, there are about 

 half a dozen species in cultivation which survive all but our very hardest 

 winters. They are of low, often spreading and procumbent habit; the 

 leaves opposite, evergreen, entire. Flowers rose-like, terminal, solitary 

 to many-flowered in the inflorescence. Petals five ; sepals three or five, 

 when of the latter number the two outer ones are much smaller than the 

 three inner ones. Seed-vessel a capsule opening in three valves. (Herein 

 is the chief distinction from the nearly allied Cistus, which has a capsule 

 \\ith five or ten valves.) Natives of Europe and Asia Minor. The genus 

 is also represented in N. America, but I have not seen any of the species 

 in cultivation here. 



Helianthemums need above all things a sunny spot. They are best 

 on some slope fully exposed to the south. Essentially sun-lovers, their 

 flowers open sluggishly or not at all in dull weather, and their time of 

 greatest beauty is in the forenoon. The flowers never last longer than 

 a day, and in the H. vulgare group they mostly close up at noon. The 

 flowers appear in extraordinary profusion, but each day's crop is suc- 

 ceeded by an entirely different one the next. They flower from May 

 onwards. Any soil of an open, loamy nature suits them ; in nature they 

 often occur on limestone. All are of easy propagation by cuttings. If 

 a mild bottom heat is available, it is preferable to take cuttings in quite 

 a soft condition ; but if they are to be rooted under a handlight they must 

 be left to get moderately firm, and put in about August. For those 

 species that ripen them, seeds are preferable even to cuttings. 



The standard work on these plants in this country is Sweet's Cistinece, 

 a book containing 112 coloured plates of Helianthemum and allied 

 genera, published between 1825 and 1830. The value of Sweet's work 

 is impaired by his method of treating all the mere garden forms as 

 species. Many of these have since disappeared. In fact, the great 

 frosts of the winter of 1837-8 destroyed a considerable number of species 

 and varieties of Helianthemum and Cistus which have not again secured 

 a place in our gardens. 



H. ALPESTRE, Dtinal. ALPINE SUN ROSE. 



(Sweet's Cistineae, t. 2.) 



A dainty little shrub, 3 to 5 ins. high, forming a tuft of dense spreading 

 branches covered thickly with pale, minute hairs. Leaves green on both sides, 

 oval-lanceolate to obovate or narrowly oblong, often "more tapered a"t trie base 



