Early flowers of the passionflower vine (Passiflora incarnata) were undisturbed by pests, but now, as dozens of Tiger swallowtails have appeared in the garden, so have Japanese beetles. Beetles find flowers as they open, and a bloom that would typically last for a few days is destroyed by midday.
There are readily available controls for beetles, and I suspect any gardener is tempted while watching a dozen of them munching on a single, newly opened flower. But, the beetles do relatively little damage, and no long term harm, so I’ll watch for the moment the flowers open to enjoy while I can.
There is somewhat more concern at the moment about aphids that have infested a shrubby crapemyrtle (Lagerstroemia indica ‘Gamad I’, below) . The infestation is in its early stages, but I’ve seen this before. The prolific numbers cannot be managed by natural controls, though there is evidence on the shrub of a variety of predators. This is a long way from the reach of a hose, and dislodging thousands of tiny aphids from beneath a thick canopy of leaves seems difficult, so the least toxic control is insecticidal soap, which I have used on rare occasion with moderate success.
There are continuing decisions that the gardener must make, when to plant, or weed, but grander decisions must be made on how his garden will be managed. Here, the first consideration is the corollary effect of my actions, so most pest damage will be tolerated so that pollinators are not disturbed.
In this garden with five ponds, the gardener’s most useful ally in pest prevention is the dragonfly. While ineffective against the crapemyrtle’s aphid infestation, they work miracles in diminishing the numbers of mosquitoes. A year ago, the dragonfly population surrounding the large koi pond was down, for whatever reasons, but numbers have rebounded this summer. At any moment, as I sit beside the pond, there will be a dozen brightly colored dragonflies zipping across the pond, with others perched on arching stems at the pond’s edge. The effect on the population of annoying Tiger mosquitoes is apparent.