Nick, welcome to the board.
I have used HP5+ quite extensively and as fschifano has stated, you can get vastly different results with different combinations of exposure and developer.
As a general rule I expose HP5+ at 320 ASA and depending on the look I wish to get, I develop it in different dilutions of D76, which is virtually identical to the Ilford ID11 developer.
With undiluted developer, I get smooth almost soft negatives. With 1+1 dilution, I find this is the nicest setting with grain noticeable but not obtrusive. When doing 1+3 dilution, grain starts to show more but it isn't overbearing either.
I use a diffused enlarger head, if you are using an enlarger with a condensor head this may show grain a bit more.
Experiment a bit and ask more questions, you'll get there.
Mick.