Have you been fertilizing this plant? A bloom booster formular will aid in forming more roots. Improved light is another consideration. I assume it is being grown outside, so heat, humidity and air circulation have been OK. You don't have that much longer a growing season, so improving watering habits would also help.

I had it outside for much of the summer. I brought it in a few days ago because we have had a couple of nights in the high fifties. I guess I will hang the plant outside in filtered light, water and mildly fertilize daily. Thanks for your help!

Rhy retusa loves lotsa light, warmth and water during suumer time. I don't feed my plants so regularly, but they get rained on. Sun and rain keeps them happy!Up the light and it may stimulate the growth.

I raise my Vanda's in Full Sun. They love it. When you get the light right, they will take off.

Rhynchostyis in general prefers a bit less light than vandas-vandas...I would not go for full sun. Though, getting the "right" light is important (just like leubafr said)

Just do your best to increase humidity, if possible...I often mount vandaceous that have no roots, or plant it in a pot with treefern chunks and lavarock - helps provide some moisture between waterings.

Olya

Undoubtedly quicksilver put the Rhy in too sheltered a spot. In MA nothing but a completely unshaded south facing location is going to work for something Vandaceous. The summer heat, humidity and air movement were of benefit as was mentioned but bottom line it still didn't receive the footcandles neccessary to stimulate growth and development. Indoors things will definitely not improve unless artificial light strategies are resorted to. Without a healthy CFL in the 85W/125W range running in excess of 12hr/dy the Rhy is toast sometime during the coming winter.

H

Thank you Howard, and all others for your help. The plant got full sun and almost daily waterings during the month of May and into early June. When that didn't work I moved it to the south side of the house under significant shade. I have had the plant in a wood box filled halfway with various orchid potting media. The media does a good job of retaining moisture, but I'm pretty sure there are no roots growing down there. (I am going to remove the plant from the box tomorrow). One of the reasons I posted here was to see if I should score the base stem before appling rooting hormone. Not a good idea - right? Thanks again folks!

When I removed the plant from the box there were no new roots. I'll give the plant more sun, water it daily, and provide more humidity by placing it in a shallow water filled container.

I have a Mokkara which had more or less the same problem. After a holiday when I had left my plants in the tender care of one of my farm workers, I returned to find that all but one of its roots had shrivelled and dried up, and that last one too was looking very woeful. This was at the height of summer so retaining moisture was also a problem.
So I got hold of some coconut fibre (easy when you live on a coconut farm ), wrapped it around that last remaining root, near the tip and tied it with some banana fibre (so it would fall off after a couple of months).
I proceeded to water it daily along with my other orchids ( it was getting watered daily prior to this too but it being summer, it wasnt really retaining it well ) and it has really taken off. There are so many nice, fat multiple roots bursting out of all that coconut fibre that it looks like an octopus-clone !

BINGO !!! Thanks tons!

I followed the advice offered by sunita. I wrapped the one root in moss, gave the plant full light, plenty of moisture and fertilizer. The plant has grown more in the last week than all the months it has been in my care. Thanks for your help!