If you have azaleas growing in your garden, you’ve probably had lace bugs at one point or another. Perhaps you didn’t know that lace bugs were the culprit but if the top side of your azaleas leaves were stippled you did. Here’s a picture…
Lace bugs are capable of turning your azalea’s leaves silver in appearance in no time. They breed quickly and can have several generations a year in the Mid-Atlantic gardening region, although two generations per year is the norm. As with most insects, the real damage is being done on the undersides of the leaves. It is here where the lace bugs reside and also where they feed. Lace bugs have piercing-sucking mouthparts; this means that they pierce the leaf tissue and then suck out the plant juice…that’s why you end up with the stippled appearance on the surface of the leaves. If you were to flip over a leaf, you’d see this:
The black shiny blobs are the droppings of the lace bugs and the lace bugs themselves look like this:
So what can you do if you have lace bugs?
- Let’s talk about prevention first. Insects are amazing creatures that have the innate ability to know when a plant is stressed. If your azaleas are in full sun, they are naturally stressed…azaleas are shade loving shrubs. If your soil is poor, add some compost each year as a topdressing to improve soil fertlity. If your soil pH is higher than 6.5, add sulfur or HollyTone to lower it. By replicating an azalea’s natural environment, you can drastically lower your incidence of lace bugs.
- A strong blast of water to the undersides of the leaves can knock the nymphs off of the shrubs and there is a great chance that they will perish before they can make it back home. The nymphs are usually present in early to mid-May (later in colder areas) so keep a watchful eye for them.
- Insecticidal soap is an effective control method if you aren’t able to control them with other methods. There are also plenty of nasty pesticides that can control lace bugs but you’ll have to do your own research if you choose this method.
It’s interesting to note that lace bugs can attack all sorts of plants: azaleas, rhododendrons, mountain laurel, sycamores and serviceberry. Don’t be discouraged if you have lace bugs on your plants…try changing the cultural conditions as noted above and then move on down the list. If you have other recommendations for treating lace bugs, please leave me a comment below or e-mail me. If you enjoy being part of the Mid-Atlantic Gardening community, join our e-mail list (upper right hand corner of this page), become a fan on Facebook and follow me at Twitter. Happy gardening!