HERBACEOUS FLOWERING PLANTS IN POTS 43 



last much longer if they are not exposed to the midday sun. 

 The majority of species can be propagated by division of 

 the crowns either in spring or early autumn. But P. sinensis 

 and those of similar habit should be cut down after flowering, 

 and kept fairly moist and warm, some of the soil being 

 heaped up round the stems. When offsets grow as the 

 result of this treatment, they should be partly severed in 

 order to induce them to form roots ; and when they have 

 done so, they should be taken off and potted separately. 

 They will flower much better than the old plants. 



Salvia. — Several of the shrubby species make handsome 

 pot-plants, especially S. boliviima, S. fu/gens, S. ruii/ans, 

 and S. splendens, all of them scarlet, the last flowering in 

 winter. Natives of South America, they should not be 

 exposed to frost. With them may be associated the her- 

 baceous S. patens^ which, though often grown outside in 

 summer, should also be in the greenhouse in winter, and 

 kept fairly dry until it begins to grow again in the following 

 season. They can be propagated by seed or by cuttings 

 taken in spring, and inserted in sandy soil in the greenhouse. 

 Young plants flower much better than old ones. .V. splendens 

 should be treated in the same way as a Japanese chrysan- 

 themum (p. 51). Salvias require a great deal of water, 

 and as they soon exhaust the soil, additional food should 

 be supplied to them by means of an artificial fertiliser. 



Saxifraga (Saxifrage, Rockfoil). — A very large family, 

 some species, like S. hypnoides (Dovedale Moss), forming 

 mossy cushions covered with white, pink, or red flowers in 

 spring ; others, like 6". lunbrosa (London Pride), growing in 

 rosettes ; and others again with the foliage in the rosettes 

 silvery or encrusted. They are mostly natives of the Alps 

 and other mountainous districts, and as the encrusted species 

 are always found where limestone is plentiful, pieces of this 

 stone should, if possible, be mixed with the soil. Indeed, 

 this is a good plan to adopt with all saxifrages, as the stone 

 absorbs water and keeps the roots cool and moist. Partial 

 shade is the most suitable position for them. The mossy 

 species are liable to be burnt up if they are exposed to strong 



