Aphids on Cup Plant

Aphids on Cup Plant

Based upon previous gardening memories we had associated aphids with hot, dry weather. So it came as quite the shock this past very wet June when our cup plants were besieged by the little red pests. For all the invading numbers the cup plants held up well showing only a little damage but we feared it could get much worse quickly. The tiny pests puncture the plant and feed on its sap, weakening it. The punctures also make the plant more vulnerable to a variety of diseases, many of which are transmitted by the aphids themselves. As a final insult, aphid saliva is itself toxic to plants.

Close-up of aphids on cup plant

Close-up of aphids on cup plant

We first tried simply knocking the aphids off the leaves with a jet from the garden hose but that provided only a brief respite. The determined hordes returned in a day or two with seemingly undiminished numbers. We must admit that once upon a time we would at this point have reached for pyrethrins or insecticidal soap or some other sort of “safe” spray but we are now obligated to think of our bees who forage on the blooms from these very plants, gathering a bright orange pollen and some nectar. Instead we turned to biological control by ordering a package of ladybugs.

Package of lady bugs

Package of lady bugs

They came in a mesh bag along with a bottle of concentrated syrup to dilute and spray onto the infested plants. A common warning with using ladybugs for pest control is that one’s neighbors may benefit more than oneself as the little things are prone to fly off immediately upon release. The syrup is intended as incentive to stay in the area long enough to discover the aphids, eat them, and make more ladybugs to carry on good fight, which they begin even as larvae. In our situation discovering aphids would not take long at all and we could not imagine them leaving such a feast of aphids soon. Nevertheless we sprayed the plants as suggested and then poured the ladybugs over them, except for a small number of the insects which we scattered in the flowers on the other side of the house. Just in case the little predators were insistent on flying then perhaps this crew would fly to the infested patch if the ones there flew away.

Bee foraging in  cup plant

Bee foraging in de-aphidized cup plant

We did not witness the expected carnage. Only a few ladybugs, so crawly in the bag, appeared to even move about on the plants without prodding. Perhaps they were savoring the syrup where they sat? At least they did not fly off immediately. Later a few immobile ladybugs were seen holding aphids in their jaws as if staging some tiny but savage tableau vivant. Those were good to see but it was frustrating that they were going about their predation at such a leisurely pace. Even so, in a matter of only a few days the aphids were gone and the ladybugs had flown off to hunt elsewhere. For all the apparent inactivity they were quite successful in ridding the cup plants of pests. Perhaps they left behind a small population near enough to prevent such a strong infestation in the future. If not, we would enthusiastically get another bag of bugs.

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