Soil mix for Greenhouse

Hi,
At the moment i got really bad quality soil so I'm gonna dig it all up and fill it with some good quality soil. Does anyone have any suggestions on what mix i should use ?
Thanks Frankie.

Happy frog,fox farm,pro mix,Or if ur short on cash Kellogg patio plus works well I have a few plants in it and they are doin great.The only thing is it could use a bit more perlite I didn't add any but you could..

How much of each should i add e.g. 50% perlite, 50% fox farm. Also are those brands available in UK, as I've heard fox farm is very hard to come by in UK ?
Thanks

oh man I dunno Im from california..If you get fox far you dont have to add any if you dont want.

Ahh i see, cheers for the help. Reped