21815 SW Farmington Rd
Beaverton, OR 97007
Each day another shrub or tree is flushing out with blooms.
Some have huge blossoms which can't be missed.
Others give a pleasant discovery only on closer examination.
Rhododendron 'Ken Janeck' Rhododendron 'Rim Fire'
Dogwood 'Prairie Pink' Dogwood 'Prairie Pink' close up
Dogwood 'Eddie's Wonder' Lilac 'Pink Perfume Boomerang'™
Azalea 'Ben Morrison' Barberry 'Golden Ruby'
Azalea lace bug, Stephanitis pyroides, has been damaging Rhododendons and Azaleas for
Lace Bug Damage
Image provided by Gardeningknowhow.com
the past several years. Severe damage by the insects make azaleas look snow white. It also affects Rhododendrons. The bug sucks out the chlorophyll from the leaves. If not controlled, the azalea weakens, drops its leaves, can no longer produce energy, and eventually dies.
It is essential that the plant is treated before or in the early stages of infestation. Once leaf damage occurs, the tissue is dead and must be removed. If your plant is fully affected and needs trimming, what would be left?
Nymphs hatch in the spring and begin feeding on the underside of the leaves. By mid summer the adults lay their eggs. Several generations may develop in one year with the final eggs overwintering.
Signs of Lace Bugs
Image provided by OSU
A gardener has several choices. Some actions would need to be repeated, but it is not recommended using all methods at the same time.
- Make sure your azalea is planted in the right area, is well watered and regularly fertilized.
- Spray horticultural oils on the underside of the leaves to smother the eggs.
- Use insecticidal soap at the nymph stage.
- Use Neem oil to disturb their growth and nervous system.
- Use insecticides to spray directly on the insect.
- Use a systemic as a preventative. We carry Bonide Annual Tree and Shrub as well as Bonide Rose Care Rx systemic insecticide. These are easy to apply, no spraying necessary and work quite well. The optimum time to use this is while the plant is actively growing.
By being proactive and regularly examining your azaleas and rhododendrons, you can fight any early infestations of the azalea lacebug. They are typically active between April 15th to July 4th, so now is the time to act, especially if your plants were affected last year. Walk around to see if it has arrived in your neighborhood. Bugs don't recognize property lines and could soon be coming your way.
Excellent information and photos can be found here
The blossoms of fruit trees and flowering ornamentals are equally attractive in the garden.
Jack Flowering Pear Cherry 'Black Tartarian'
Blueberry 'Bountiful Blue' Blueberry 'Northcountry'
Azalea 'Hino Crimson' Pieris japonica 'Passion'
Mahonia aquifolia - Oregon Grape Rhododendron 'Ramapo'