| This is a good time to explain sunburn better.
Your plant does not sound like sunburn. Sunburn will usually be on the upper-most leaves. Lower leaves are dying from old age. Sunburn will develop where the suns heat can build up, this is usually the point where the leave bends. On an Oncidium alliance plant this is always the case. On a den the leaves do not bend noticeably.
I grow my dens outside under 50% shade cloth in SW Florida. Probably 3-4 times the light level of your window (and twice the recommended level). Dens do not burn easily.
The last point applies to more then just burn. Hobbyist need to learn that the short answer in this and any forum or advice from a dealer, is not the only possibility only the most common.
If it was really burn the burn area would have turned light brown, the burn area would have shrunk very thin on a Den compared to the rest of the leaf, and it would not have fallen off. Burned leaves look bad but never kill the plant or the leaf. The unburned area is still as good for the plant as any other leaf.
The good and bad news is the same. Dens often loss a lot of leaves especially after being brought home the first time. The recover and do just fine. Relax a little and enjoy the plant.
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jerry  |