TUBEROUS BEGONIAS. 



349 



over-pot the plants. Most double varieties will do well in 6, 7, or 

 8-inch pots unless the tubers are large. If, later on in the year, the 

 plants appear to have outgrown their pots, they can be given a shift 

 with great advantage at any time during the summer, even if they 

 are in bloom, and the blooming period of the plants will be greatly 

 prolonged. Singles require more pot room than doubles, and some 

 of them will fill an 8 or 9-inch pot well. Watering must be well 

 attended to from the beginning, and especially the first three weeks 

 after repotting. The plants will be benefited by an application of 

 manure water once a week when the pots are getting full of roots and 

 they are beginning to bloom. They are gross feeders, but it is better 

 to give them liquid manure often and not too strong. Soot water is 

 good for them and should be given alternately with some good animal 

 manure. It is important to remove all buds until the plants are well 

 established and the pots are fairly well filled with roots. All side buds 

 should be removed from the doubles at as early a stage as possible. 

 This will increase the size of the flowers and there will be less tendency 

 for them to droop. 



Seedling tubers, one year old, or early cutting tubers of the previous 

 year, give the finest flowers, but for specimen plants two or three- 

 year-old tubers would be most suitable. 



It is not a common practice to propagate single Begonias by 

 cuttings, as they are obtained so easily from seed, but this method of 

 propagating is indispensable for the named double varieties. Cuttings 

 are taken at any time during the summer, either of the shoots that 

 spring directly from the tuber, or of the side shoots ; but in either 

 case care must be taken that there is a dormant eye at the base of 

 the shoot, immediately beneath which it must be severed or the cutting 

 will not form a tuber. The cuttings will strike readily if placed 

 in a propagating frame and kept close. They are best inserted at 

 the sides of the pots in a compost made up of equal parts of loam, 

 leaf-mould, and sand. They will make root in about a month, when 

 they should be gradually exposed to light and air. The young plants 

 will be greatly benefited by a shift into 3 or 4-inch pots, using soil 

 similar to that recommended for tubers. 



Tuberous Begonias are subject to attacks of green fly, Begonia 

 mite, and eel-worm. Green fly can be easily kept under by the 

 ordinary methods of fumigation. The Begonia mite is the most 

 insidious foe the grower has to fear. Its presence is detected only 

 when irreparable damage has been done to the plants. It is then 

 recognizable by the brownish appearance of the under sides of the 

 young leaves and the points of the shoots, which gradually turn black, 

 wither, and die. The growth of the plants is completely stopped, and 

 they are quite spoiled for the season. (For many years this was 

 treated as a fungoid disease.) Plants that are found to be affected 

 should be immediately isolated and sprayed with a strong insecticide. 

 The remainder of the plants should be vaporized with nicotine com- 

 pound, three times in succession. However, prevention is better 



