Phaius Tankervilliea with dark tips on leaves
 

I bought this "nun orchid" last year in full bloom and kept it in my sun-room in an east-facing window. It is now re-blooming, but over the winter, the ends of the leaves turned dark brown, almost black, and some of them looked as though they had been shredded by a cat. What could be causing this?

During the winter months, we keep the room open to our living area, and we have a small gas-log heater which we leave on during the day. It is not vented, but I always open a couple windows for ventilation. Could this be the problem?

Mine did the same last year ....I discovered I was keeping it too dry.

This year leaves are very nice but they are going to get ratty as new growth comes out and they die back.The old leaves are shed after new ones come along

Phaius Tankervilliea with dart tips on leaves
 

My Phaius also has blackened leaf tips. I have no idea why. It also has eight spikes getting ready to bloom. I'm going to put it into our April show and before I take it I will trim off the black tips. I keep it outdoors in the summer and in the GH in the winter.
Beverly A.

I also purchased one last year in full bloom and it is reblooming this year. I do not have any black or darkened leaf tips though. While I'm not sure why you guys are experiencing it, I thought I might give you guys an idea of what I've done. Perhaps between knowing what I did and what you guys did we might be able to figure something out. Please remember though that I'm not saying what I'm doing is the right way! lol...

I kept it in a relatively cool basement (lows in the lower 60s, high's in the mid 60's). It was under grow lights and was getting about 4000 footcandles if I remember correctly (I have since moved it into the living room so I can see it). There was no air circulation other than a single vent in the ceiling, but honestly it doesn't do much for the basement in terms of air flow.

I did not leave a water tray under it or expose it to much humidity. I believe the humidity in my basement stayed around 30 to 40% unless it rained or snowed. I watered it twice a week. If the soil was still really moist from the previous watering, i would just give it a "refresher" of water as opposed to a heavier watering.

When I brought it indoors, I made sure to put time release fertilizer in the pot.

I can't think of anything else I really did for it.

I have one that has spikes & I am waiting for the blooms. Patience, patience.

Mine is starting to drop the first flowers now. I think maybe 8 or 9 total have fallen. But there are still about 60 or so more flowers, and about 10 that haven't even opened up yet! It's been a great show and well worth the patience!