Without a photo we're trying to play a guessing game Agripa22. Black spots suggest a fungus, you often get wasps in gardens.... dunno, sorry.

Loads of wasps around the bush might just mean they have a nest either in the bush or somewhere nearby and what you're seeing is the constant activity around it. Check the area to see.
As for the black spots, knowing what the plant is does matter - certain plants are subject to certain diseases, so it is always helpful to know what plant it is. Photograph would be very useful if you don't know what its called.