A New Podocarpus? No, Just Aphids!
I spotted a podocarpus in a landscape with attractive curly new growth. I thought to myself, “is this a new variety with a unique characteristic?” As I came in for a closer look, I saw the telltale signs of aphids.
The podocarpus aphid is a pest of the nonnative ornamental shrub Podocarpus macrophyllus. It is easily recognizable by its blueish purple color. Podocarpus aphids tend to aggregate on the stems and leaves of their host plant. They feed on only one host plant during its lifecycle. The mature aphids appear in the spring, summer, and fall. Large populations of podocarpus aphids can cause stunting and curling of new growth and can lead to honeydew build-up and sooty mold formation on the plant.
Aphid populations are often reduced by natural enemies such as predatory beetles. If damage to plants becomes severe, the following control measures may be used: insecticidal oils and soaps, contact insecticides, and systemic insecticides (based on label recommendations for the location of the plant). Oils and soaps are most effective on low infestations of podocarpus aphids. They are most effective when applied directly to the host plant three times, with seven to ten days between applications. It is important to not apply oils and soaps when it is hot and sunny outside or the leaves may be damaged (a condition referred to as burn). Be sure to follow the label instructions on all insecticides.