44 MISSOURI BOTANICAL GARDEN BULLETIN 
removed as cuttings and placed in sand with bottom heat. 
The cutting should be made through a node or just below 
it to insure proper rooting and development of tubers, two 
to three weeks usually being required for rooting. Seed 
propagation is a simple method, but the results are very 
unsatisfactory due to the hybrid character of the parentage 
and is not advocated for the amateur except as a means of 
production of unstable novelties. 
The distance apart for planting varies with the varieties, 
but for general purposes three to four feet are usually left 
between plants. The time of planting has been a matter 
of dispute, but there is little doubt that early lanting is not 
as satisfactory as late. To flower properly the wood must 
be young and succulent, this condition being obtained only 
through a continuous period of growth without a check. 
Early-started plants are severely checked by the heat of mid- 
summer and either fail to flower at all or are killed by frost 
before flowering. Heavy pruning of woody plants may re- 
sult in sufficient rejuvenation to produce flowers. The last 
of May or early June is considered the best period for 
planting. 
Light soils are best suited for dahlias, the original home 
of the genus being the sandy plateaus of Mexico. On very 
light soils manure or other humus-producing substances 
should be introduced to wr the moisture-holding 
capacity, while heavy soils should be lightened by the intro- 
duction of sand, lime, sheep manure, or bulky straw manure. 
Further treatment of dahlias after planting consists of 
training them in one of two ways: (1) They may be al- 
lowed to develop unrestricted, a stake being driven to each 
= to support the stem; or (2) the terminal shoots may 
e pinched out after three to four pairs of leaves are formed, 
this checking the terminal growth and ‘lag oven heavy, 
stocky stems capable of self-support. This latter process 
naturally delays the blooming period for two weeks and 
removes the largest of the flowers, but by judicious disbud- 
ding the size of the other flowers may be increased suf- 
ficiently to serve all needs. 
Thorough cultivation to conserve moisture is essential. 
A mulch of leaves, grass clippings, or well-rotted manure 
may be used during the summer for this purpose. Water- 
ing should only be practiced if done regularly, the ground 
being thoroughly soaked at intervals depending upon the 
weather. Mere sprinkling of the ground is deleterious, 
though spraying of the tops during particularly hot weather 
is beneficial. 
