OF THE DAHLIA 27 
soil has been constantly and thoroughly cultivated, 
thus regulating the moisture content of the soil, the poor 
plants have been alternately soaked in water and cooked 
in dry earth — an experience sufficient to ruin them for 
the rest of the season. The dust mulch greatly lessens 
the harm likely to be done by repeated extremes of 
weather, and if the dust mulch never fails the threatened 
check in growth can be prevented. 
In August a surface mulch of stable manure, es- 
pecially valuable if it is strawy, will keep the surface 
soil cool and prevent evaporation, and help the blooms 
whenever rains or irrigation wash some of the manure 
into the soil. Lawn clippings, spoiled hay, any litter 
that does not contain too many ripe weed seeds or plant 
diseases, or insect pests, are also excellent mulches. 
Cultivation with rake, hoe, or horse drawn imple- 
ment is the one rule that has no variation, and applies 
equally to every locality and to all climates. Conditions 
differ so greatly over an area as mighty as that of the 
United States, that few rules can be formulated that 
apply with equal force everywhere. As a rule dahlias 
should not be watered. Yet in the dry, cloudless 
seasons of parts of California irrigation is absolutely 
necessary, and in various other sections of the United 
States if overhead piping or hose facilities allow, judi- 
cious applications of water make the difference between 
jj exceptionally fine blooms or poor and indifferent 
■flowers. Observe your plants carefully, note their 
