SEABROOK NURSERIES GLADIOLUS 
CONTROL OF THRIP 
If you had thrip this year do not throw your bulbs away as they will not be 
harmed in any way whatever. Just treat in napthalene, disinfect in the spring 
and they will be perfectly all right for another year. 
The Thrip found on the gladiolus during the past two years appear to be 
black with cream colored wing bases, having a banded appearance and are about 
1-16 inch in length. This plant provides a wonderful hiding place for Thrip as 
they live inside the folded leaves and florets unnoticed by some until the flower 
droops, others may observe a silvery sheen on the leaves where the insect has 
sucked the juice out of the leaf, during the very early stages of the plant. 
The control of the insect must be done mostly through the treatment of the 
bulbs during the storage period for they will live over on the bulbs, if kept in a 
warm temperature. 
At digging time the tops should be removed, being very careful not to shake 
the tops over any of the stock, and burned. 
Bulbs should be stored in a room where the temperature is no higher than 45 
or lower than 32 degrees. Two months before planting time, sprinkle Napthalene 
flakes at the rate of 1 pound to 1000 bulbs or 1 ounce to about 100 conns among 
the bulbs and allow fumigation to continue until the conns are planted. 
As another precaution, soak the bulbs in lye at the rate of one can of lye 
to 25 gallons of water for 12 hours just before planting. This will kill any insect 
on them and will aid in preventing scab or rot. This solution must not be used 
any stronger. 
There is little that can be done to control the attack of this insect in the 
garden. A garden which has had gladiolus for years, with never a sign of Thrip 
may be infested by a person bringing it on his clothing. High winds will carry 
them from a neighbor’s patch to yours. Infested bouquets of flowers may be 
taken from one state to another. Careful inspection of plants should be made 
once a week, by folding back the leaves to determine whether any thrip are 
present. The flower spikes should be inspected also as they form. Start inspect¬ 
ing the minute they come out of the ground. 
If thrip should appear, use a weekly spray of one rounded tablespoon of 
Paris green, two pounds of brown sugar and three gallons of water well mixed. If 
a stronger solution is desired, which is harmless, use 2 tablespoons of Paris green 
instead of one, to the same mixture. Some have substituted cheap molasses in 
place of brown sugar, which is good. The solution must get into the folded 
leaves to do the most good. Should thrip appear in the young flower spikes, cut 
them down to four or five inches above the ground and burn them. Then spray with 
the Paris green mixture the remaining stalk. 
Sometimes where the gladiolus plant has been well watered, keeping the 
soil fairly moist, the plant will grow rapidly enough so that it has time to bloom 
before the thrip could injure it. 
Pass this information along to your neighbors and friends who are lovers of 
gladiolus that they, too, may help destroy this pest. 
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