Phaleonopsis with many Blooms, Leaves Suddenly Yellow!

[rowdymagic]

Forgive my ignorance, I am new to orchids. I believe the one I have is a phaleonopsis.

I repotted one I was given about 6 months ago in orchid mix and it blossomed out beautifully, has about 40 blooms (photo attached). I water it thoroughly once a week, and it has holes for drainage in the bottom of the pot.

However, in the past week or two, suddenly the leaves are turning yellow, and one leaf has a whitish patch on it (second photo attached). Is this some kind of insect? Disease? Too much sun? Normal die-off? There is also a new leaf coming in in the middle - is this just replacing the others, which are naturally dying off?

I live in Southern CA and it has been pretty warm until the past couple of weeks - about the time the orchid's leaves began to turn yellow. The plant gets full sun through a window for about half the day, but it is cooler now. What would you suggest?

[turock]

Welcome to the forums, and what a beauty! you are correct, this is a phalaenopsis.

The yellowing of the leaves looks to me like symptoms of heat stress. Sometimes this can take a little while to show up. The white patch looks very much like sunburn, or possibly a patch of water that stood on the leaf, got too hot, and cooked it.

I'd say put a shade cloth or sheer curtain over your window and back the plant away about 6 inches or so. If you have a little desk fan, you might let it gently blow on the orchid during the hottest part of the day to let it cool off.

Unfortunately, the white patches will eventually blacken, and will never recover. That's ok, though, many of us have sun-marred plants. It may be a good idea to sterilize some scissors and cut off the sunburnt portion of the leaf, so that it doesn't get a secondary infection through the compromised tissue.

The yellow parts of the leaf should green back up again with adequate cool and a bit lower light.

Good luck!

[rowdymagic]

Thanks so much! The sun has been quite bright until recently, so it would make sense that it was a little too much for the plant. I will move it back and see how it does. Your wisdom is much appreciated!

[turock]

Glad to help! Update this post if you see anything else that worries you, or if the yellow continues to spread after several days in the shade.

[estación seca]

Welcome to the Orchid Board! What a beautiful plant!

Phalaenopsis are shade plants. In the southern parts of the US they should never have sun shining directly on the leaves, not even through a window. They should be close to the window but not where sun will hit them. A sheer curtain is usually good enough to protect them.

Don't be too upset if the yellow leaves die completely - they sometimes don't recover after a bad burn. The plant should grow new leaves if you treat it well.

There is a whole thread on growing Phalaenopsis in the Beginner forum.

[rowdymagic]

Ah, thanks for that information! The orchid was a gift from my vet when my dog passed away last December, and I am determined to keep it healthy and beautiful. I haven't ventured into orchids before, so I appreciate all of your help and advice.

The sun has shifted here recently with the time change and the move into fall, so the plant has been getting even MORE direct sun than in summer, when it was hotter, but the sun was higher overhead and more end-of-day (and we had the a/c on). It sounds like the recent change was way too much for it. I will rearrange things so that it will not get direct sun.

I recently rescued 3 near-death orchids, same variety, from work that had been left outside untended by the owner, so I will follow your advice as I try to bring them back to life, too. Thank you so much!

[turock]

This is one of the best of the beginner care articles that estación seca mentioned: The Phal abuse ends here.

I'm glad you're determined to keep your plants happy. The most important step in that process is researching what conditions they like the best. Orchids are very tough and will put up with a lot while you learn how to listen to them.