I dont recognise which plant this is. Is sirocco a variety name. Or do you mean Sarcococca [sweetbox] that flowers in the middle of winter.

if its Sarcococca then it will be fine in multi-purpose or your own garden soil.

Yeah, sorry Sarcococca, it's not me my keyboard is dyslexic. LOL

its my fingers I type with my middle finger faster than with my ring finger. haha

The reason I asked, is because I already have a bag of ericaceous. There's no need for me to go out and buy Multi-purpose if I don't have to. I just thought it would save me time and money if I can utilise what I already have.

Yes they should be ok in Ericaceous compost according the the RHS they are not fussy on soil pH.