Missouri Botanical 
Garden Bulletin 
Vol. V St. Louis, Mo., October, 1917 No. 10 
FORCING PLANTS AND TWIGS 
The forcing of hardy herbaceous and woody plants has 
been practised for a number of years on a commercial scale, 
but it is not generally known that for home purposes, where 
forcing structures are not available, twigs of flowering trees 
and shrubs may be brought into bloom during the winter 
and serve to add a distinctive and unusual effect to home 
decoration. Before discussing the methods employed in 
forcing plants and twigs, it is essential to have a concep- 
tion of their condition of dormancy or rest at the time of 
forcing. 
The rest-period of plants may be defined as the time when 
all outward activities appear to be at a standstill. It usually 
begins in the fall with the advent of conditions unfavor- 
able to growth and continues until these conditions are im- 
proved in the spring. In the case of deciduous trees and 
shrubs, the rest-period actually begins when the length 
growth ceases and the terminal buds form. This may take 
place as early as July, the plants gradually becoming more 
and more dormant until complete defoliation takes place. 
The herbaceous perennials begin to rest after their tops die 
down in the fall and crown buds are formed. Bulbs enter 
their dormancy within two to four weeks after flowering, 
when the tops yellow and die. The length of the period of 
rest varies with the different species; some are ready to begin 
Bebe in a few weeks; others are unable to start for several 
months. 
The period of dormancy may be broken or shortened by 
means of various treatments. Plants with long rest-periods 
are difficult to arouse during the early stages, but the greater 
part may be readily forced during the middle portion of the 
ose Among the agents employed are ether, drying, 
reezing, submerging in warm water, immersing in weak 
alcohol, mechanical injuries, the use of weak solutions of 
hydrochloric and tartaric acids, etc. 
(145) 
