Sorry Ctheh could you amplify your question as an answer. So far as I am aware ivy does not encourage wasps.

I have ivy on my house and have never had a wasp problem.

The wasps might cut the leaves for their nests, thats all, anyway wasps left alone are good for the garden, they mop up, hoover and clean around the garden, we should just leave them be.

I've answered the question you asked above. Wasps love the food provided by ivy flowers. There is no problem because of this.