Without any particulars on your orchids, a basic bark mix is available
at most box stores that sell orchids. Locally Walmart stocks Schultz.
Lowes stocks Better-gro, New Zealand sphagnum as well as other orchid
suplies. Both bark mixes are roughly 5 parts bark, 1 part perlite, 1
part charcoal. That works well for most epiphytics.

Terrestrial and Semiterrestrials may need an ammendment. A 60-40 (or
70-30) bark mix with African violet mix or a better potting mix
(Miracle grow or Moisture control) have worked well for me in the past.
It isn't complicated and any potting medium you select will need to be
soaked before you repot into it anyway.

Otherwise, an online search of ingredients you may want to use will
give several sources. Most will have a mix available as well as
individual ingredients. Shipping charges will often exceed the cost of
small quantities of the mix. Specialty mixes, i.e. Coco husk chips
(CHC), coir fiber, Clay aggregates for Semi-hydro (S/H), coarse
perlite, or charcoal isn't readily available at the box stores.

I've ordered different potting mediums from different suppliers because
they specialize and I get better value. Even if you could get to a
garden center that had supplies for orchids, the prices may be higher
because of the quantities they order and the shipping prices they pay.

The big issue is whether you can match whatever you use to your growing
conditions, or reverse that statement. Do whatever you do, evaluate
the progress and refine it based on your results. It's embarassing to
have an orchid grow on the compost bin after you threw it out because
you were sure it was dead from your best intentions.

Best wishes,

Nancy


Peter A wrote:
Can anyone recommend a good source for ready-made orchid potting mixes?

Thanks

--
Peter Aitken