GROWING DAHLIAS 
FOR CUT FLOWERS 
Any good farm or garden soil will produce a satisfactory Dahlia crop. Select an exposed, 
sunny location free from tree roots. Dahlias make a lot of growth throughout the season and 
therefore require a lot of feed. We suggest one ton of good potato fertilizer to the acre, broad- 
cast and disced in before planting, followed by one or two applicatons through the season of 500 Ibs. 
per acre. Dahlias also want moisture but they must be planted on soil that is well drained. Any 
rain that submerges any part of the plant or root for more than a few hours can prove fatal. To 
maintain the plants in a good growing condition they should be irrigated on dry soils when the 
rainfall is less than 1” per week. 
The planting season depends on climactic conditions. The roots will start to grow as soon 
as the soil is warm in the spring but subsequent plantings can be made as late as June. Do not, 
however, plant on very hot days for a soil temperature above 70° may cook the tubers. 
Planting is simplified by opening straight furrows six inches deep and three feet apart. Place 
the tubers horizontally in the direction of the furrow, eyes-up, all facing the same way. Space 
large flower varieties 2 feet apart and the miniature and pompon kinds about 18”. Cover with 
about two inches of soil and depend on subsequent cultivation when the plants are up to fill 
the depression or even ridge them after they are a foot tall. 
With the plants in straight rows hand cultivation is reduced to a minimum. After the plants 
are a foot tall cultivate not more than two inches deep every week or as often as necessary to 
eliminate weeds and maintain a dust mulch. 
Staking and tying the plants is desirable with small plantings. It is, however, quite costly 
and therefore not generally practiced by commercial growers who prefer straightening the plants 
after rain and wind storms. 
Large-flowered Dahlias require systematic pruning to produce good flowers on long stems. 
When the plants have formed their second pair of full-sized leaves, cut out the center shoot 
just above the crotch of the upper pair. (See illustration.) Soon after the first pruning four 
laterals will be growing from the axil of the four leaves. 
Before the next pruning ‘step is taken the grower must decide on the number of flowers 
wanted per plant. The greater their number, the smaller the size. For four flowers of the largest 
size remove all further side shoots as they appear, If eight flowers are the goal per plant the four 
laterals are cut back just above their first pair of leaves. This will cause the growth of two 
secondary laterals from each. The number of flowers could be doubled by treating the secondary 
laterals in the same way as the primary ones. 
All Dahlias form more than one flowerbud at the end of each branch. With large flowering 
varieties only one should be permitted to remain. The center one usually is chosen because it 
is the first to open and also the strongest. Pinch out all others. With miniature and pompon 
varieties these side buds can remain and make additional flowers. 
INSECTS AND DISEASES 
In most sections the Dahlia leafhopper is the worst pest with thrips a close second. Both 
are sucking pests easily controlled by keeping the plants covered with DDT. One pound wettable 
50% DDT powder to 100 gallons of water together with a good sticker-spreader will give nearly 
perfect control if applied as a fine, forceful spray which will settle on all parts of the plants. This 
material also takes care of the corn borer and tarnishing plant bug. 
While most growers can identify thrips readily, the Dahlia leafhopper, which is also called 
Potato and Apple leafhopper when found on these plants, is less familiar to many despite its 
rating as the number one enemy. They rest on the underside of the leaves and when disturbed 
the young ones move quickly, often with a characteristic side motion which suggests skidding, in 
order to reach the other side of the upturned leaf. In their winged adult stage they will disperse 
from disturbed plants like a miniature cloud of dust if the infestation is severe. The sucking 
causes the leaves to curl and buckle, and they also become discolored. 
Both the Dahlia leafhopper and thrips carry virus diseases and their prompt destruction all 
through the growing season offers the only effective means of keeping the plants free, or nearly 
so, from these damaging diseases 
There is no known cure for virus diseased plants. These are quickly recognized by the stunted, 
off-color appearance. They should be pulled out and destroyed 
Flowers should be cut preferably in early morning. Remove all foliage from the part of the 
stem which will be under water as it will turn black and start decay very quickly. Short-stemmed 
varieties will keep in good condition if sprinkled with water and kept between layers of wet cloth 
or paper; others should be plunged deeply, in cold water. Flowers which fail to revive promptly 
can be restored by making a slanting cut of the stem under water. 
H I! 
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pee 
PLACE TUBERS IN FURROWS 
G INCHES DEEP, EYESUP AND 
ALLFACING THE SAME WAY 
_Z-CENTER SHOOT 
ABOVE SECOND 
BEC PAIR, 
LATERALS 
HAVE GROWN 
FROM THE 
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READY FOR SECOND PRUNING 
SEE TEXT FOR DETAILS 
PAGE SEVEN 
