I don’t know personally, but I love bees so I looked up the answer. Here’s what I found:

Can diatomaceous earth harm bees the way it harms other insects? We get this important question a lot. The short answer is yes, it can harm them. But it doesn't have to. It is possible to apply diatomaceous earth for pest control and still keep bees safe.

As you might already know, DE is effective on insects because of their exoskeletons. DE scratches off and absorbs the waxy, oily coating on an insect's exoskeleton, which eventually leads to death by dehydration. DE can have this effect on bees too, however, bees have at least one advantage–possibly two–that protect them from the effects of DE.

The first and most obvious advantage bees have is that they are flying insects. For DE to take effect, an insect has to crawl through it. Because bees are mainly airborne, they are far less likely to come into contact with DE than other pests, such as ants, cockroaches, and bed bugs. So applying on soil, concrete, and other areas level to the ground shouldn't be a problem. It's also safe to apply to plants as long as you follow these precautions:

• Don't apply DE on blossoms or on foliage immediately surrounding them.
• Only apply on the stems and leaves of plants if you don't see bees crawling on them.
• If bees start crawling on the stems and leaves of a plant you have already applied DE on, spray it off with water.
• Apply early in the morning or late in the evening when bees are less active. This will help bees avoid contact with clouds of DE dust that may puff up as you apply.
• How to Apply Diatomaceous Earth without Hurting Bees