f 
been en route for five or six days may be acclimated to open air conditions by set- 
fing them in the shade for a day or two after they are received. We do not recom- 
mend washing the soil off the roots before planting as is sometimes done. We have 
found that shallow planting of plants is conducive to better clump formation. For 
this reason we recommend that the ball of soil surrounding the plant in the pot be 
covered with no more than an inch of soil when planted in the garden. 
Many failures with "GREEN PLANTS" are due to improper cultural methods at the 
start of the growing season. Normal growth should be the aim. It is not uncommon for 
the gardener to employ all methods within his knowledge to get his plants off to a fast 
start. A fast growth is also a soft growth which is easily injured by the heat and dry 
weather of mid-summer. Such injuries result in a check to the plant and a resultant 
hardening of the plant tissues. When the tissues become hard, or woody, they lose their 
properties to expand, or grow. Thereafter, no greater amounts of plant food can pass 
up through the stalk than was the case when the hardening took place. Growth prac- 
tically ceases. When this has occurred, first class results can be obtained only by 
cutting the plant back to the ground and starting all over. In many cases this will be 
too late to obtain blooms. 
Hardening may also be caused by a number of other factors. In some cases the 
condition may have been inducted by planting too early, when the soil is too cold for 
normal growth. Some other factors which may cause this condition are: setting plants 
in the garden which have not been properly "hardened off" in cold frames, allowing the 
plants to dry out, excessive water, lack of cultivation, root injuries due to insects or 
fertilizers, as well as a number of others not so common. When growth has been normal 
the plant can cope with conditions which would cause a soft plant to suffer a check. 
Cultivate once or twice each week to a depth of five or six inches in the early part 
of the season. Right next to the plant cultivation should not be as deep or some of the 
roots are likely to be cut off or injured. When the plants are in bloom and the spaces 
between the plants are pretty well filled with foliage no further cultivation will be 
necessary. 
Water only in very dry weather. One thorough soaking is far better than several 
light sprinklings. Frequent watering brings the roots too near the surface where they 
are quickly injured by heat or drought. More water will be required after the plants 
start blooming than earlier in the season. 
There are a number of elements in the soil which are needed for proper plant 
growth. Of these elements there are only three which are likely to be present in lesser 
amounts than needed by the plant. They are NITROGEN, PHOSPHORUS, and POT- 
ASH. In order to arrive at an intelligent fertilizer program we must understand the 
purpose of the above elements to the plant. 
NITROGEN is needed for bush growth, dark green foliage, and large flowers. 
Plants growing in soil which is lacking in nitrogen show a yellowish cast to the leaves, 
low growth, failure to develop buds properly, and small flowers of poor color. Too much 
of this element produces a tall growth, soft plants, delays blooming, weakens stems, and 
reduces the keeping qualities of the roots in winter storage. It will injure leaves and 
roots if applied directly, or too close, to them. The common sources of nitrogen are 
cover crops, dried blood, fish scraps, barnyard manures and commercial fertilizers. 
PHOSPHORUS is the most important from the dahlia grower's standpoint. It is 
essential in all plant functions. It hastens blooming, increases root development, stiffens 
the stems, increases the general vitality of the plant, and it overcomes the harmful 
effects of excessive nitrogen as well as certain other adverse soil conditions. Phosphorus 
is not harmful even when applied in excessive quantities. The common sources are: 
super-phosphate, double superphosphate, and bone meal. The latter also contains a 
small amount of nitrogen. 
POTASH increases the general vigor of the plant, it is essential in the chemical 
changes occurring in the plant, and root formation is dependent upon its presence. The 
common sources are: muriate of potash, and sulphate of potash. Hardwood ashes are 
sometimes used as a source of potash but are not to be recommended owing to their 
vairability in potassium (potash) content. 
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