This is a very common but minor boxwood insect pest called psyllid. They do not need treatment, but if bothersome, you can use a strong spray from a garden hose to knock most of them off. The white material is a waxy residue produced by the insect to protect itself from the elements and to hide from predators. It will also go away on its own in time if left alone.

The older damage visible on the foliage -- the fine etching marks -- is from boxwood mites. (Not the same species as the spider mites found on other plants, like annuals and tropicals, but they feed in the same way.) They too are a minor pest, though here their feeding damage looks more extensive than we usually see. That might be due to a previously applied pesticide (if you had sprayed or soaked the roots to target another insect in a prior year) or the plant's growing conditions. Mites tend to thrive in areas with reduced air circulation, like plantings close to a foundation wall or solid fence, where heat can build up during summer and/or roots dry out faster. Boxwood roots are relatively shallow compared to other shrubs, so they are more vulnerable to drought during dry weather spells or in situations where the soil is not mulched.

You can learn more about each of these issues on our boxwood diagnostic page. The good news is that a blast of water can knock mites off as well, though nothing can heal damaged leaves. New growth will eventually cover them up, though, and in time it's natural for the plant's oldest leaves to shed, so one way or another, the damage won't be permanent. Some boxwood cultivars are more vulnerable to certain pests or diseases than others, which might be why some plants develop more damage than others (or their exposure to breezes, sun/shade, or soil moisture is slightly different).

Miri

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