Hydrangea flowers are rich sources of pollen and nectar and will attract flying pollinators like various bees, flies and some species of wasps. They do not attract houseflies, hornets, yellowjackets or most predatory wasps, as these are primarily carnivores or carrion or garbage eaters and do not often feed on nectar nor utilize pollen.

Flowering plants attract pollinators - that is one of their primary reasons for being and the reason why most flowers are as attractive as they are. Flower color, shape and form are designed by Mother Nature to attract whatever creature she has intended to assist in fertilization. If you do not want the pollinators, you have to remove the plants or at least the flowers or relocate them to where they won't be a nuisance for you.

I don't mind the pollinators in the bushes. Bees are a part of life :) The real problem are the hornets and the houseflies. It is a really strange combination... I would like to get some sort of housefly trap, but I do not want to trap all of the honeybees. Maybe I should just leave it alone. I was just worried because there were so many that they would infiltrate the house and destroy the plant.

My Quickfire is always covered with flying insects liek that. They don't do any damage, but you can hear the buzzing as you approach. Same thing with Little Lamb, but not to the same extent.

A. They won't "destroy the plant" whatever they are.

B. If the plants are attracting houseflies and hornets, then there is something else going on. These insects are NOT attracted to plants unless the plants are scented like decaying flesh, which hydrangeas most definitely are not (some common plants are).

Perhaps there is something else nearby that is causing them to be present. Houseflies and hornets are attracted by garbage: meat scraps, ripe/rotten fruits and vegetables, pet excrement, etc. Or perhaps the hornets have established a nest nearby.....many are ground nesters. You could try trapping - hornet and yellow jacket traps are safe to use around bees, as what attracts these insects is not what attracts the bees or other pollinators.

My Tardiva invites the same insects. There is nothing wrong with the plant nor am I worred about it but it does HAVE common flies on it. Along with a few flying ants, bees and wasps.

Along with the Bees and Wasps, Butterflies are also attracted to the nectar. I have counted as many as 6 species of Butterflies, including the lovely Monarchs, on a H.p. 'Limelight' near my kitchen window. Even the little Hummers check it out!

I avoid that area during the daylight hours, as some species of Bees are very aggressive around their nesting sites. Been there, and have painful memories of that!