COSMOS | 283 
luxuriance of foliage and poverty of flowers. The taller varieties should 
be planted at the back of borders, and well staked. For beds the smaller 
kinds, such as the Pompones, are more suitable, and these may be 
improved for the purpose by pegging down the branches. The so-called 
“doubles” yield little seed, and are mostly raised from cuttings or 
divisions of the roots. The “singles” produce seeds freely. These should 
be soaked in water for a few hours before sowing them on pans of light 
earth in March. The pans should be placed in gentle heat ; the seedlings 
potted singly, and hardened gradually before planting out at the end of 
ay or beginning of June. Cuttings are made from the young shoots 
soon after they start from the tubers, which have been placed in heat in 
February for the purpose of starting growth. When the shoots have 
two joints they are removed and potted singly in sandy leaf-mould. 
In a close frame these soon emit roots and need repotting early, prior 
to being hardened off. They will be ready for planting out in June. 
Almost any number of plants may be raised from a few tubers in this" 
way, by syringing the roots and inducing them to throw out a succession 
of shoots. Another method of propagation more frequently adopted in 
‘small gardens is to start growth from the collar of the undivided tubers 
by placing them in heat in March, and then separating the tubers, 
taking care so to divide them that each has its own shoot. If these are 
potted singly, and grown on until June, they will then be vigorous 
plants for setting in the open ground. Grafting is also resorted to for 
the propagation of delicate varieties. When the tops of the Dahlia- 
plants have been blackened by autumnal frosts, they should be cut 
down to within half a foot from the ground, the roots lifted with a fork, 
and the bulk of earth clinging to them removed without injuring the 
tubers. They should then be dried in the air, and stored in a cool, dry 
place until required for re-starting in spring. In so moving them care 
should be taken not to separate the tubers from the old stem, for it is 
from this part that the new shoots will break. 
Description of Leaves and flower-heads of Dahlia variabilis showing 
Plate141. colour range. The characteristic double involucre is well 
seen in the bursting bud at the top of the Plate. 
COSMOS 
Natural Order Composit&. Genus Cosmos 
Cosmos (Greek, kosmos, an ornament). A small genus of annual or 
perennial herbs, allied to Dahlia, with which they agree in the 
