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 draught. 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 POTASH. 
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 push growin, dark green foliage, and large tiowers. 
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 
variability in potassium (potash) content. 
As a general thing, it is advisable to broadcast an 0-20-20 fertilizer over the 
garden about two weeks before planting. Five or six pounds per hundred square feet 
of space is a good application. It should be thoroughly mixed into the soil when dig- 
ging as the phosphate element is not readily moved down into the soil by water 
action. In some instances, owing to unfavorable soil reactions, it may be advisable to 
concentrate this application in the hole as it is prepared for planting. In this case, 
mix a good handful of the fertilizer in the soil under and around the plant. Avoid 
having any of the fertilizer in direct contact with the roots. This latter method will 
often remedy the failure of plants to make good clumps of roots. 0-20-20 is a commer- 
cial fertilizer formula indicating; no nitrogen elements, 20 per cent phosphorus and 
20 per cent potash. 
In average garden soil it will not be advisable to apply a nitrogeneous fertilizer 
at planting time, but if experience has proven that satisfactory growth early in the 
season is not possible without it, a small amount of barn-yard manures (well rotted) 
may be mixed with the soil at planting time. Nitrogen fertilizers are more satisfactorily 
used later in the season, after buds are formed, to give extra size to the blooms. 
A small quantity scattered lightly around the plant, not nearer than a foot from the 
stalk, and watered into the soil will decidedly increase flower size. One or two more, 
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