What are these Black spots on my leaves? - Orchid Board

raimeiken · #1 03-18-2009, 04:39 PM

I got these black spots on the leaves of my Angraecum didieri

any idea what it is and what could've caused it?

King_of_orchid_growing:) · #2 03-19-2009, 12:54 AM

For me it usually is a sign that the orchid was grown under an incorrect temperature range.

I'm not sure what it would be called.

It's harmless unless it keeps spreading. If it keeps spreading it could be a bacterial or fungal infection.

King_of_orchid_growing:) · #3 03-19-2009, 01:01 AM

BTW I'm not necessarily saying that your orchid is currently grown under incorrect temperatures, just that it probably was at one point in time or possibly even currently.

You have to provide more details on how you're growing it.

raimeiken · #4 03-19-2009, 01:11 AM

i guess it just happened recently. I have a photo of it when I just got it new and there's no black spots on it

It's sitting near the top of the tank were it's a bit warm. Should I move it somewhere a bit cooler?

King_of_orchid_growing:) · #5 03-19-2009, 02:06 AM

How warm exactly is it? A number would help a lot.

When you unpacked the plant, was it exposed to the cold? Was it snowing where you live? How did the package arrive?

Also, what's the humidity? Number please.

Is there air circulation (computer fan)? Is it an open top tank?

How bright is the light? What kind of light are you using? How long is the light exposure?

raimeiken · #6 03-19-2009, 02:20 AM

definitely wasnt snowing here. The place I got it from delayed to ship the plant due to cold weather over there, but when I got the plant it didnt have any of those spots. So it's probably because of the conditions Im putting it in.

On where it's at in that pic, it probably get to about mid or high 80's Humidity stays between 70-90+ throughout the day. Air movement in that spot isnt that great.

After reading around the web, I've read that this plant likes it drier. The spot it's at right now get a lot of misting so I moved it somewhere where it gets more air circulation and less water.

Hopefully it'll get better.

King_of_orchid_growing:) · #7 03-19-2009, 02:25 AM

I hope so to.

The problem with your plant doesn't appear to be severe anyways. It seems to be growing new roots which is always a big plus.

I wish you the best.

Ross · #8 03-19-2009, 08:14 AM

It's an early sign of rot in the leaves. The plant looks too wet to me. Mine are kept out of the misting system (yet still in high humidity) and very high light. Those spots will advance until the whole leaf falls off. Now is a good time to move the plant out of constant moisture and give it a dose of Thiomyl.

beanluc · #9 03-19-2009, 10:51 AM

Quote:

Originally Posted by Ross

It's an early sign of rot in the leaves. The plant looks too wet to me.

I agree. I see spots of standing water on the leaves, both now and when it was new, and I see slick of wet all over the whole plant. Interestingly, the water beads are about the same size and shape as the rotspots... eh?

BL

raimeiken · #10 03-20-2009, 11:48 AM

Quote:

Originally Posted by Ross

It's an early sign of rot in the leaves. The plant looks too wet to me. Mine are kept out of the misting system (yet still in high humidity) and very high light. Those spots will advance until the whole leaf falls off. Now is a good time to move the plant out of constant moisture and give it a dose of Thiomyl.

where can I buy Thiomyl?