Don't Give Up!

This summer I learned the meaning of patience and persistence. I have a lot of house plants, 22 in fact; and some of them are fairly large (i.e., five to six feet tall). Naturally, with this many plants, the chances of one or more of the plants getting a parasite increase. I made the mistake of not placing newly purchased plants in quarantine to ensure they didn't have any parasites before integrating them with the older plants. Apparently, one of the new plants had whiteflies or something similar (I'm still not quite sure which insect it was, but based on the symptoms, my plant books indicates whiteflies). At first, I thought only one or two of the older plants were infested. Over a period of several weeks, I began to notice a lot of insects hovering around more of the plants. You guessed it: ALL of the plants were infected! I tried the standard insecticide used for vegetables and ornamentals that are infected with whiteflies.

I diligently sprayed all of the plants two or three times a week to no avail. So, I read my plant books again. The insects were laying their eggs in the potting soil, and the newly hatched flies were emerging from the BOTTOM of the pots! No wonder the spray didn't work. Since the problem was in the soil, the books recommended Malathion. This insecticide is poured directly in the soil killing the larva and adults. I isolated the plants in groups of four or five for several reasons. First, Malathion smells terrible, so I applied it in a spare bathroom, which allowed me to shut the door and also prevented the odor from permeating the rest of the house. Second, I let the plants stand in the Malathion for several hours before draining the water. These plants were then left in the bathroom for at least 24 hours. After 24 hours, I moved that group of treated plants into a separate room and closed the door. After approximately four days, I had watered all of the plants with Malathion. I had four or five plants in all rooms in the house. I felt that this would help prevent all of the plants from being re-infected. I hoped, if one of the plants within a particular group was still infected, it would only re-infect that group of plants. At first, I thought I had eliminated the insects. When I tapped the pots, a lot of dead whiteflies fell out of the bottom. I also managed to flush out some other insects I didn't know were there. A few days later, I still saw some whiteflies emerging from the bottom of some of the plants. To be safe, I applied the Malathion to all 22 plants again. After the second Malathion application, four or five plants were still infected. This time, I moved only those plants back to the bathroom and applied the Malathion a third time. This time, the plants remained in the bathroom. I closely watched these plants and was able to further identify the two or three that were still infested. They got a fourth dose of Malathion. In the meantime, the other groups of plants stayed in separate rooms. Each day, I tapped all of the pots to see if any live or dead whiteflies emerged. Any that had live flies were immediately moved back to the bathroom and doused with Malathion. Eventually, after four or five weeks, I saw no further evidence of whiteflies. I'm keeping my fingers crossed, but since this summer, I haven't seen any more insects. Sometimes persistence and patience pays off.

Author: 
Karen Brown
Issue: 
November, 1997