it does depend on the species really. Generally they tend to prefer neutral to acidic soils. The one I have 'Susan' needs a top dressing every year as my garden is alkaline.
So which one is it that you have?
The link below will give you suitable advice.
https://www.rhs.org.uk/advice/profile?PID=599

welcome to GoY too :o)

Definitely not alkaline, in my experience, though only a few species will grow where I am.

They do well here, so must like it slightly acidic. Ive grown Soulangeana, loebnerii Leonard Messel and Stellata types and they all do fine as long as you can keep them away from strong winds.

My Stellata does fine on pH 6.5