Earlier today I was "browsing" in my local nursery and so as usual I left with two orchids...
A Cattleya and a tiny little Phal (label says 'Little Lady'). I've got a couple of mini Phals already but this one is like a mini mini Phal. I've never seen one so small!! So obviously I bought it.
Yes, it will stay this small. Mini hybrid Phals take the same care as larger hybrid Phals. There is a wide range of hybrids bred from miniature species. Breeders recognize lots of people grow on windowsills and would like much smaller flowering plants.
__________________ May the bridges I've burned light my way.
I am unfamiliar with this hybrid but would caution you not to assume (and you obviously didn't since you posted this Q but as a note to the public at large) phals sold blooming at this size will remain that way. It is not uncommon for phals to be sold as small/young blooming plants which will, over time, get substantially larger.
Yup, I've got two Little Ladies myself and they stay just like this, a friend of mine keeps them suspended in tea cups.
Perhaps a fair note of warning that they dry out more easily - smaller plant, smaller root mass, hence smaller pot/container and far less medium. Thus the medium dried much faster and the roots may dry out faster too. You may have to water it more frequently or use a more retentive medium. This is the only phal I grow in something other than 100% bark. It is usually sold around here with its roots wrapped round a block of peat moss or packed in sphagnum, in tiny plastic pots with a half inch deep reservoir at the bottom to improve humidity and prevent suffocation.
I have a white one which is on its second year blooming. It has perhaps grown slightly bigger (both leaves and flower spikes) but not by much. It is still much smaller than a 'small' Phal.