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 ere 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 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 ■■oot 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. 
To reduce the foregoing to a simple fertilizer program we suggest spading under 
an application of bone meal (steamed) at the rate of five or six pounds for each one 
hundred square feet In the garden. This may be done two or three weeks before planting 
time. The plant food element in bone meal Is very slowly available and one application 
will last throughout the season. Potash may also be applied at this time at the rate of 
two or three pounds per one hundred square feet. Since bone meal also contains a 
small amount of nitrogen (3 to 4%) none will be required at this time. Nitrogen being 
a quickly available plant food It may be applied later in the season, or just when it will' 
be of the greatest benefit. 
For increased size of blooms apply nitrogen just after the buds have formed. In this 
simple sample program we will use dried blood. Scatter it between the rows at least a 
Foot from the base of the plant at the rate of about two pounds for each one hundred 
square feet. Cultivate it into the soil and water well. This application may be repeated' 
in three or four weeks, but no more than two applications should be given. Properly 
fertilized plants are less susceptible to attacks of diseases and insects. 
We have found that dusting sulphur (300 mesh) applied to the under side of the 
leaves with a dusting gun or sprayer Is an effective control for a number of insects es¬ 
pecially leaf hoppers and red spider. In our gardens we use no other spray material. If 
insects are taking their toll In your garden have your local seedsman recommend a spray 
material for your special problem. Many Insects are discouraged from attacking a plant 
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