Grammatophyllum fungus or bacterial

[littleflower]

Got this orchid 4 days ago, it had a black spot on one leaf tip so I cut it off and sprayed with physan. Four days later, that leaf looks worse, and another is involved. Pleas help, this is my first grammatophyllum and I don’t want to lose it!

[estación seca]

We would need detailed information about your growing area conditions and how you are watering it.

[littleflower]

Ok, in the last four days, I watered Thursday when I got it, and today when I got home. Is it out on my screened porch, I am in George’s so it’s been pretty hot and humid

[estación seca]

Grammatophyllums should grow extremely well in a humid and warm climate like yours. Watering twice a week might not be enough. They don't like to dry out during active growth.

Is the plant making one or more new growths now? Are the spots on older growths, or on new growths? Did you put the plant where it gets direct sun shining on its leaves at any time of the day?

[littleflower]

There are 4 Pseudobulbs, The leaf problem is on 2 different Pseudobulbs, but not the newest growth. it may have gotten some direct sun (I was actually gone for the weekend) but it would not have been for long. As far as watering, it feels pretty moist right now. It’s kind of hard for me to tell with all of the roots, pic below

[estación seca]

From the photo it looks in great shape to me. You have a really nice plant. Scratches and bumps from shipping can turn black. If you go out into the garden and look around, a lot of leaves on everything will have damage and small black spots.

Most greenhouse-grown plants can't go straight into full summer sun, but most of the Grammatophyllum species can probably be moved slowly to where they get direct sun for at least several hours per day.

I would water it every day, even in your climate. In a warm, humid climate Grammatophyllums are hard to rot. Give it a lot of fertilizer, too.

Note that they drop old pseudobulbs by having them turn brown and squishy. They then dry up. This frightens people who haven't grown them. I've never seen this spread to newer pseudobulbs; it's just how they drop old growths.

[littleflower]

Thank you so much, I feel better about this already!!! I will water every day. Any thoughts about repotting? Wasnt going to disturb it now unless you think it needs it. Also, with those leaves, should I just wait and let them fall off on their own?

[estación seca]

You could repot any time it is in active growth. This genus is more vigorous than many other orchids. I would choose a pot 4"-5"/10-12cm larger in diameter than the current pot. It keeps leaves for multiple years, so I would not cut them off.