Finally, with a few cooler nights the chrysanthemums are showing more color. There have been other years too when bloom has been significantly delayed such as the hot, dry year of 1991 that ironically became abnormally cool in early November when temperatures plunged to 12º F! Although some relief from the drought has arrived in rainfall and somewhat cooler temperatures, more rain would be needed to end the dryness deeper into the ground.
With the hot weather, insects have been producing more generations of young which in turn has caused problems with plants. One significant insect is the lacebug which attacks azaleas (deciduous and evergreen) as well as small-leaved rhododendron such as PJM. The adult which appears to be a small clear-winged fly, can be found on the undersides of the plant’s leave’s. The nymph stage of this insect does the real damage as they pierce the underside of the leaves to extract the plant’s fluids while it turns the leaves to a bronze-like color instead of the usual verdant green. This invasive bug was a problem for the south for years as it was first observed in mobile, Alabama in 1927. About 10 years ago, I first observed an infestation of this insect on some beautiful Azalea Boudoir in Barberton, Ohio.
For heavy infestations, spraying the plants now with an insecticide containing the active ingredient called acephate will kill adults and nymphs with the acephate’s systemic qualities. A follow up spray about 10 days later will finish off the second generation that will hatch from eggs as the eggs are not affected by the acephate. Afterwards, the plants must be sprayed right after bloom in spring and another repeat spray about ten days later to keep them free of the lacebug. One such trade name for acephate is called Bonide Systemic Insect Spray that is a concentrate to be diluted with water at a rate of 1½ fluid ounces of Bonide to 1 gallon of water to be sprayed on the plants to the point of runoff. Other brands of this insecticide might have different dilution rates due to varying amounts of concentration so that with any insecticide it is imperative to follow the directions on the container. Another plus to using acephate is that it is not a neonicitinoid that will harm beneficial pollinators such as honeybees and bumble bees that might visit blooming plants.
For sure the chrysanthemums will color beautifully but it remains to be seen if Ohio will be painted with colorful changing leaves or if the dryness of this summer will affect the color.
Que sera sera.