I'm a little (!) late getting back to this, but I thought I should report.
I started using Orchiata based on some early responses. I've been very happy with it.
I, too, am now trying to avoid sphagnum. It's great when new (good texure, lots of sugars), but is really only very helpful for about 6-9 months. Thereafter it's a bit like having sponge in the mix. Water retention, yes, but there are other ways of dealing with that.
Regarding sources: I currently buy from Quarter Acre Orchids and have been very happy with the service. (She also ships her large quantities from Arcadian Supply which is very local, so I do get good shipping charges.)
|