Hi Bev & Joclyn!
The charcoal that we use for our barbeques is manufactured specifically, to be used as fuel... treated with petroleum products to assist in ignition & long burning. DO NOT use it as orchid "potting soil"!
Wood ashes will thicken when it's wet (& be sort of like masonry mortar), & will coat the orchid roots, preventing the needed air from getting to them.
"Orchid mix", available in most stores where regular potting soil is sold, consists of redwood or fir bark, coconut fiber, charcoal, lava rock (or a number of other things that will ensure thorough drainage), & is fortified with nutrients specifically beneficial to orchids. Yes, it's VERY expensive, considering that it doesn't seem to come in small bags. (I wish it were available by the quart, rather than in 8 quart bags... which is the smallest I've found. 8 quarts will last FOREVER, unless you've got LOTS of orchids!)
If you can't find someone who would care to split a bag with you ...or sell you the amount you need from a bag that they've bought, the only thing I can think of is that you make your own potting media from small pieces of a clay pot. (Not "ideal", but as close as you'll probably get, without the risk of using something that has been sprayed or treated with insecticides or herbicides.)
Be sure to use orchid food (only), & follow the directions on the label, closely. ("Less is More" when it comes to feeding orchids, as it's easy to burn the roots with heavy or improperly diluted applications.)
You might want to read what I posted last week, in Jon's Propagating Orchids
I have the moss, spag.......
And that is all i can see in my orchid plant.
Personally, I would add some (probably not "all")
of that moss, in with the chunks of clay pot. Remember, you don't want anything near those roots that will be soggy & prevent aeration.
Good luck with your orchid, Bev!
(How are yours coming along, Joclyn?)
Now that school is back in, I'm starting to get caught up on things, & will mail your requested seeds
off to you as soon as I can.