328 ROCK GARDENS 



be advisable. Primulas hybridise so easily that new varieties are 

 constantly being put on the market, many of which have but a 

 botanical interest. A selection, which will be found on p. 334, has 

 therefore been made of the best and most distinct kinds not included 

 in the above list. In this country at least, Primulas, though 

 theoretically perennials, are but short-lived ; it will therefore be 

 necessary, in order to keep up the stock, to raise plants from seed, 

 which should be sown as soon as ripe ; for, if kept over the winter 

 many kinds may take a year, or even longer, to germinate, if they 

 do so at all, 



P. algida. — Bog-loving ; in peat and loam, in half shade. Obtuse 

 leaves, finely toothed. Rich violet-purple flowers. Rather rare and 

 difficult to keep. Increased by seed, when it can be obtained. 

 Nearly allied to P. farinosa. 



P. Allionii. — Requires gritty loam and plenty of moisture at its 

 roots. Plant in vertical position, or under ledge of rock, so that no 

 moisture can lie on its leaves, which are very susceptible to damp. 

 Of compact habit, forming cushion-like tufts of rather hairy leaves. 

 Flowers rosy-purple, with a pale centre, on short stems. A very 

 choice plant, but of difficult culture. Increased by seed or division, 



P. amoena (syn, P. cortusoides Sieboldi). — A half-shady and 

 sheltered position in rich, rather moist loam. Forms tufts of 

 rather rugose leaves, with umbels of violet-coloured flowers on stems 

 about 6 to 7 inches high, in April. Of vigorous growth, increased by 

 seed or division. 



P. auricula. — The Auriculas may roughly be divided into two 

 groups. The one self-coloured, with leaves and other parts 

 smooth and not powdery. The other has flowers and stems 

 thickly coated with a white, powdery matter. Of the first group, 

 those known as alpine Auriculas are the hardiest and most suitable 

 for the rock garden. The second group are mainly florists' varieties, 

 and are more delicate. They have again been divided into different 

 sections, according to the colour of the edge of the flower ; but I do 

 not propose to deal with these subtleties, and shall take only the 

 alpine section. The other kinds can of course be grown, and a 

 selection should be made of the most distinct and hardiest varieties. 

 The P. auricula., the parent of all these numerous varieties, is by no 

 means common. It is a limestone plant, and should be grown 

 wedged in between rocks in a vertical position, in partial shade, A 

 good, rather stiff, loamy soil suits it well. It has glaucous, rather 

 fleshy leaves, and yellow, sweet-scented flowers, borne in dense 

 umbels on stems 4 to 5 inches high. 



The variety P. a. ciliata (syn. P. Balbisii) has its leaves edged 

 with granular hairs, and its yellow flowers are scentless, and not 

 farinose. 



