USEFUL GREENHOUSE PLANTS 161 



greenhouse plants in winter and spring. The seed should be sown about 

 midsummer, and as soon as the young plants are large enough to handle 

 they must be pricked off. Then pot them singly into small pots, and as 

 these get full of roots the plants may be shifted into pots five inches in 

 diameter, in which they will flower until the end of September. A cold 

 frame is better than the greenhouse, but before autumn frosts set in 

 they should be removed indoors. The double-flowered varieties are 

 increased by surrounding the stem with a mixture of moss, loam, and 

 sand, into which they will root, and as soon as they are sufficiently 

 advanced the plant may be divided and the several pieces potted. The 

 propagation of double Primulas requires considerable care. With regard 

 to the single varieties, unless they are needed for seed the plants may, 

 after flowering, be thrown away, as young plants give better results than 

 old ones. A good soil for the Chinese Primula is two-parts loam to one- 

 part each of leaf-mould and decayed manure, with a liberal sprinkling 

 of silver sand. In all stages of growth the watering of these Primulas 

 must be carefully done, as an excess of moisture or of drought is equally 

 fatal. Pretty semi-double flowers can be readily obtained from seed if 

 it is saved from a good strain. Besides this, several other Primulas are 

 valuable for the greenhouse, notably, the Auricula, which blooms in the 

 spring, the Japanese P. cortusoides Sieboldi, of which there are many 

 pretty varieties, flowering at about the same period, and 



Primula floribunda, which produces its pretty golden blossoms almost 

 throughout the year, while the sulphur-coloured P. verticillata sinensis 

 flowers in the spring. A continuous blooming form is the pretty mauve- 

 coloured P. obconica, which has led to much discussion at different 

 times owing to its leaves when handled in some cases causing an irrita- 

 tion of the skin, while others who handle it are quite unaffected by it. 

 The Star Primula (P. stellata) is a name applied to a very graceful 

 form of the Chinese Primula; it is quite a break away from the 

 ordinary kind. It is taller and more slender in growth, the whole plant 

 being far more elegant than the ordinary Chinese Primula. 



Rhododendron. This is a large group of beautiful flowering shrubs, 

 many of which do not flower until they have grown to a considerable 

 size. Some of the hybrids, however, flower well in a small state, among 

 the best being Countess of Derby, Countess of Sefton, Duchess of 

 Sutherland, Lady Alice Fitzwilliam, and Princess Alice. All of the 

 above have large white or blush-coloured and very fragrant flowers. 

 These Rhododendrons need the same treatment as their near relatives 

 the Azaleas. All of them flower during the spring months. 



Richardia. The most popular of the Richardias is the Arum Lily 

 (R. sethiopica), also known as the Lily of the Nile. It has very hand- 

 some white trumpet-shaped spathes, which are in great demand for 

 wreaths, vases, and similar purposes. The foliage, too, is conspicuous, 

 and good plants form a striking feature in the greenhouse. The flower- 

 ing season varies according to the treatment given, but in a general way 

 these big white spathes are most appreciated in winter and early spring. 

 To obtain them stand the plants out of doors during the summer, and 

 keep them dry for a time. Then about the middle of July shake them 



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