Aphids make tropical milkweed less inviting to monarch butterflies, study finds

Many gardeners will tell you that aphids are the bane of their existence. According to a new study from the University of Florida, these tiny pests also pose problems for the iconic monarch butterfly. The study found that when oleander aphids infested tropical milkweed—a nonnative milkweed species commonly used across southern portions of the U.S. stretching from California to Florida—the butterflies laid fewer eggs on the plants, and caterpillars developing on those plants were slower to mature.