Lowe's will have orchid mix, if you go that route. Like Lin, I don't measure too much, just look for the mix I feel is right. Potting mixes at Lowe's will have some perlite and most orchid mixes you will find there will also have some perlite, perhaps some coconut fiber, and Douglas fir bark. The orchid mix will be a pretty small bag, so just get a bag of potting soil that is perhaps 3x as large and you should be fine. Get a small bag of Osmacote (they probably won't have but the one, general purpose kind), to save yourself from fertilizing often with water soluble fertilizer.
