Looks like it's doing really well as it is, Ken. Maybe it will need re-potting at the beginning of the summer though. Mine was very happy in just regular potting mix (the big one) and stayed in the same pot I bought it in for a couple of years.
If they are outdoors where they can catch lots of bugs, they don't need much nutrient from the soil. If yours gets a little bit of orchid fert sprayed over it occasionally while its in your greenhouse, I'd think it will keep it very happy. Once it's outside and the weather is warm, it will take off.
