52 THE CULTURE OF POT-PLANTS 



the roots have filled the pots, a weak fertiliser should be given 

 every few days. When the buds appear it may be advisable 

 to thin them, but for decorative purposes the number of 

 flowers is of more importance than individual size. The 

 plants should be brought into the greenhouse before they 

 are likely to be injured by frost — usually about the end of 

 September. The chief pests are the chrysanthemum fly, 

 aphides, mildew, and rust. The fly deposits its eggs on the 

 leaves, and the tiny maggots, when hatched, bore their way 

 inside and make whitish marks. The position of each insect 

 can easily be seen, and it should be crushed. Badly marked 

 leaves should be taken off and burned. Spraying the plants 

 with water containing a dash of paraffin will keep the flits 

 away. For aphides, soapy water or any other insecticide 

 can be used, and for mildew or rust a weak solution of 

 sulphide of potassium (liver of sulphur), not more than h oz. 

 in I gal. of water. Indoors, where this liquid would blacken 

 paint, the worst leaves should be taken off and the others 

 dusted, when damp, with flowers of sulphur. Chrysanthemums 

 in small pots are often useful for rooms. They can be 

 obtained by striking cuttings in March, or later. 



Coronilla. — The two best species for pots are C. glauca 

 and C. viminalis, the former with pea-shaped yellow flowers 

 produced throughout the whole season, and the latter with 

 pale red. They should be kept dwarf by pinching off the 

 tops of the shoots when necessary, and must not be allowed 

 to get dry. They can be propagated by seed or by cuttings 

 in spring. 



Correa. — A genus of shrubs w^ith red or white tubular 

 flowers. They should be treated in much the same way as 

 azaleas, except that, after flowering, the shoots should be 

 shortened. In warm weather they should be frequently 

 sprayed. 



Cytisus. — The plant commonly grown in pots under the 

 name of genista is really C. racemosus. Another fine species 

 is C. Ardoini. There are also some beautiful hybrids or 

 varieties, notably C. Andreamis (crimson and yellow) and 

 C. kewensis (cream). In order to keep them in good shape 



