Jack, as per the usual AFN way, you have gotten some great advice.
The quality of advice and ease with which it is given is a pleasure to see.
So, now for my ten pence worth. You may have seen my outdoor UK grow which isn't too shabby. I did not use any special compost or nutrients (Chempak veg + Bloom) nor did I fuss over them too much. It will mostly depend on the weather. I had two auto's that crept into my photo grow and they were superb (if I say so myself). They will lap up loads of nutes when outdoors and love the natural rain. Just keep them out of frosts during the early weeks, ie end of April/early May and you can't go wrong.
Check out other outdoor grow threads and absorb.
Don't tell anyone else, but (it is actually real easy and you get loadsa rep that you don't really deserve. I know, I did!) Keep schtum and enjoy!
eP.