Our hibiscus sprouted a beard overnight. I mean, a full Claus: long, whispy, perfectly white. And amazing circular patterns on the underside of leaves, tight mazes that remind me of cave drawings. Like some OCD faerie spent the night hanging off the branches, drawing the same intricate image over and over and over. An infestation by the Giant Whitefly, which has been making its way north from San Diego since 1992. I admire the creativity of the insect world, even when I don’t like it. I spent the morning pruning our beautiful plant – the creepiness of the experience enhanced by the fact that our neighbor, a composer, was playing music like you’d hear in a 1950s horror movie, less about thunderous sound than about atonality and unpredictability, with sudden high plinking. Gods and Monsters indeed.
The best management is first to cut infested parts away, then spray with a sharp stream of water to knock off any you missed. Other things may help, like feeding the plant with worm castings. I’m always grateful to our California extension programs, which provide such useful information on how to deal with unexpected things like beards on your hibiscus, in the least toxic way. Here’s their page on the Giant Whitefly. The spirals are wax deposited by the adults as they walk on the leaves (presumably doing their morning walking meditation in a labyrinth in their minds). The hairlike filaments are assumed to protect their eggs. But they also simply astonish. http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7400.html