Question
I have an Moth orchid and it has been doing very well in my dorm room window but one day it was very hot out and there is a burn on one of the leaves. I have left it and the leaf is green all around the burn but it look bad can i cut if off with out killing it? Is there a certain way i should cut it off? Also the leaves below it are getting yellow so i was wondering if i should cut those off too. This is my first orchid and it has allot of new buds like allot and they are growing quickly i don't want to mess it up before they bloom. Please help!


Answer
Dru, you may cut the burned leaf below the burn spot.  Probably best to use a clean razor blade, then, seal the wound case by the blade with sulphur, roottone or other powdered fungicide.  I'm concerned about the lower leaves turning yellow which is a sign of root rot.  If the roots supporting those leaves have collapsed, the leaves will continue to turn yellow and fall off.  This is a different situation from your burned leaf.  In this case, the problem is in the roots and the leaf is the symptom. If it is root rot, which I strongly suspect, the entire  plant, including flower spikes are at risk.  While I don't normally recommend repotting when the plant is in spike, this should be investigated.  See if you can locate a small bag of orchid potting mix (Lowes and Home Depot garden centers may have this) and bring planning to repot in fresh mix.  Then, unpot the plant and examine the roots.  If there are collapsed roots these are dead and need to be removed before repotting. I suggest you soak a portion of the fresh orchid potting mix before use and repot the plant with its good roots in the fresh potting mix. Since the risk of losing the new flower spikes is less if you repot it in fresh potting mix to get more roots started, thyis is a good gamble.  If the current potting mix is sour, replacing it, could save the plant and might not affect flowering substantially.  But even if repotting has an adverse effect on current flower spikes, they may have been lost anyway and you may save the plant.