"NC" wrote in message
...
Chris Hogg wrote:
AIUI, JI-1, -2 and -3 are all the same basic mix but with increasing
amounts of fertiliser (NPK).

Does anyone know where JI-Ericaceous fits in the series?



A quick google gives:
http://www.gardeningdata.co.uk/soil/...john_innes.htm

Interesting:- Looks like JI ericaceous is similar to JI seed compost .The
difference is that limestone is replaced with sulphur to give a higher pH.
I have never used JI but I suppose perhaps I end up making something
vaguely similar by mixing soil with bog standard seed and potting compost.