H. quercifolia , or oakleaf hydrangea, is a handsome shrub with large oaklike foliage that turns a reddish-purple in fall. The large clusters hold creamy white flowers that turn pinkish with age. So far, so good. I had two hummingbird feeders that I had to take down because the bees absolutely swarm all over them. The little birds didn't have a chance.
Bees can be pests at the sugar-water feeders.
About all you can do is move the feeders in hopes that the bees will loose track of them or buy feeders with bee guards. According to information from a Web site on hummingbird feeders, it was recently discovered bees are attracted to yellow. If you have a feeder with yellow on it, you might try removing any parts that are yellow and see if this helps. Remember to wash hummingbird feeders once a week with hot water and a bottle brush. Fill with fresh sugar solution.