IRISES AND TENDER BULBS 235 



plislied early enough in the autumn to permit 

 the newly planted roots to become thoroughly 

 established before winter sets in. The rhi- 

 zomes should never be planted deeper than an 

 inch below the surface, unless the situation is 

 unusually dry. As the clumps increase in size, 

 divide them by cutting the rhizomes sharply 

 with a spade or similar implement, transplant- 

 ing the portion detached and allowing the par- 

 ent plant to remain in its position undisturbed. 



TENDER BULBS 



There is another class of bulbous, tuberous- 

 rooted plants which is worth considering and 

 which, like those requiring planting in the fall, 

 are easily grown. These are the bulbs which 

 bloom in summer and autumn and are planted 

 in spring. They are known as tender bulbs 

 because they will not endure the winters, but, 

 after blooming and ripening, are dug up and 

 stored away to be replanted the following 

 spring. Among the most important species of 

 this class of bulbs are the agapanthus, al- 

 strcemeria, tuberous begonia, bessera, canna, 

 caladium, cooperia, crinum, dahlia, gladiolus, 

 madeira vine, montbretia, oxalis, calla, tigri- 

 dia, tuberose, and zephyrautiies. 



