DAHLIADEL NURSERIES 
• Grow 
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^DAHLIAS, 
CULTIVATION 
By cultivating at least once a week, twice prefer' 
ably in the early season, and as soon after rain or 
irrigating as the ground can be worked, the weeds 
will be held in check and a soil mulch formed which 
will conserve the moisture and lessen the need of 
irrigation. 
As the plant develops and the feed roots come 
toward the surface, the ground should be worked 
rather shallow around the hill for the radius of at 
least a foot. Still work the balance of the ground 
rather deep and bring some fresh soil to the plant at 
each cultivation, giving the plant a new supply of 
food and protecting the surface roots from the heat 
of the sun. Have the hills mounded 3 to 5 inches 
by middle of September. This will help support 
the stalks and protect the roots from freezing should 
an unexpected cold spell catch you before digging. 
PESTS 
THRIPS are tiny insects which in the nymph 
stage are less than Vs of an inch long and a greenish 
gray color. They enter the growing leaf bud and 
chafe the newly formed leaves, injuring them so that 
they develop malformed and curled, also injuring the 
small flower buds and stems. These insects seem to 
enjoy the life blood of certain varieties on account 
of its flavor and do not molest the adjacent bush. 
If the attack is not checked the leaves will be gnarL 
ed and twisted, the buds onesided or so injured that 
they dry up and fall off. This usually results in a 
stunted bush, which in reality is only debilitated by 
insect ravages. 
LEAF-HOPPERS are larger than thrips and of a 
pale yellowish green color, a little over Vs of an inch 
in length. They fly when the bush is touched dur' 
ing the heat of the day. These sucking insects do 
much to keep a plant from getting a good start. 
APHIDS (plant lice) are soft'bodied, sucking in' 
sects which usually work on the under side of the 
leaves in groups, causing the leaves to curl. Thrips, 
leaf'hoppers and aphids are possible common carriers 
of virus diseases and should be kept in control for 
this reason, if for no other. 
CONTROL. We recommend the following spray. 
For thrips and leaf'hoppers use 2/3 oz. (4 teaspoon 
fuls) of Pyrethrum Soap to 1 gallon of water, with 
the addition of Blanck Leaf 40 at the rate of 1 to 2 
teaspoonfuls to the gallon of spray, according to the 
ability of different foliage to resist burn. This kills 
not only by asphyxiation, but also by the toxic ac¬ 
tion of the pyrethrum. 
For plant lice use 2 teaspoon fuls Pyrethrum Soap 
to 1 gallon of water. Black Leaf 40 is not necessary. 
For Japanese beetles and other hard'shelled insects, 
also red spider, use 8 teaspoonfuls Pyrethrum Soap 
to 1 gallon of water. Black Leaf 40 is not necessary. 
Should a bush be infested with ants, spray bush 
and pour a few quarts of the Pyrethrum Soap spray 
Japanese beetle strength down the ant hill, or 
enough to fill the hill. This will do the dahlia no 
harm, but kill the ants. 
Do not mix more than you are going to use the 
same day. This spraying can be done at any time 
of day regardless of weather conditions, except rain. 
Another control of thrips, leaf'hoppers and aphids 
is dusting with a good 3% nicotine dust. Apply in 
sunshine with the temperature above 70 degrees at 
weekly intervals as a preventative from the time the 
plants are set or roots start to grow, and if any 
should appear then about every four days until they 
are controlled. For small plants a paper funnel on 
the end of the duster spout, held over the plant for 
about one minute when dusting, will increase the 
kill materially. 
During windy weather when dust cannot be ap' 
plied to advantage, overhead sprinklers used during 
the heat of the day will control red spider and check 
the leaf'hoppers and thrips. See “Irrigation.” 
By dusting or spraying before the presence of in' 
sects, it is doubtful if you will see any. As it is diffi' 
cult to procure nicotine dust and pyrethrum soap in 
most localities, we are listing them under “Dahlia 
Growers’ Supplies.” Page 48. 
RED SPIDER in late years has caused consider' 
able damage to dahlias. This insect is barely dis' 
cernible with the naked eye and works with such 
rapidity that you may have a row of dahlias today 
and within a few days or a week all the lower leaves 
will be as brown as cured tobacco leaves. There will 
be a very fine white web in evidence on the under 
side of the leaf. These insects multiply very fast in 
dry, hot weather, do not like strong air currents, and 
cannot stand cold water, especially applied with pres' 
sure. Syringing or spraying will help in their con¬ 
trol. A spray of one level teaspoon of Colloidal 
Sulphur to one quart of water will be found very 
effective, and two sprays two or three days apart 
should clean up the infestation entirely. 
CUT WORMS are easily controlled by scattering 
about a teaspoonful of poison bran bait around the 
plant (but not touching it) as soon as plants are set 
or shoots appear from roots. The early evening is 
the best time to apply it. 
2 tablespoonfuls of molasses or brown sugar (dis' 
solved). 
1 level teaspoonful of paris green mixed in. 
Juice of an orange or equivalent in water. 
1 quart of bran or enough to make a reasonably 
dry mash. 
COMMON STEM BORER. This black'and'white 
striped worm when small enters the stem just above 
the ground and usually works upward. It will be 
noticed in the early season by the shortening of the 
internodes and later on by wilting. When noticed 
early, cut the plant off near the ground and get the 
borer with your knife. If the borer is below where 
you want to cut back, use a hooked wire from the 
top. A plant cut back not later than July 15th 
should be in full bloom early in September. Wax 
or plaster paris may be used to close up top of plant 
after borer is out so water will not get in and rot 
the plant. 
Should a plant be too large to cut back when bor' 
er is discovered, use pyrethrum soap at strength of 
8 teaspoonfuls to gallon and inject with ear syringe. 
This will kill the borer or drive it out. Drain stalk 
out by slitting at the bottom to prevent stem rot. 
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