Yellow Spotting on Vanda

[lzel924]

Wondering if anyone can help me figure out what is going on with this vanda. It’s in a tree near three others and the others don’t have this issue (which just started). It’s in spike. Someone suggested to wipe the spots with a wet cotton ball to check for mites. I did this and it was clear. Any ideas? The backside of the plant has the yellowing but not nearly as much as the front in the photos. It is on one leaf of another vanda nearby both are in spike.

[rbarata]

Phyllosticta capitalensis also known as Guignardia?

[SouthPark]

I reckon that - maybe it's a good idea to just try something if the spread appears to be occurring quickly. Such as spraying something like mancozeb everywhere on the plant. This is regardless of whether the issue is both on the outside and inside of the plant.

For all these plants - maybe occasional application of weak cal-mag spray to the roots (eg. each month) could provide some resistance to things like this. Hard to say though. But certainly something is better than nothing.

[aliceinwl]

Is there any chance it’s sun or cold damage? I have a young Vanda I got last year with a single patch that looks a lot like the damage on your plant. The patch on mine hasn’t spread and I assumed sun or cold damage had occurred previously.

[SouthPark]

Originally Posted by aliceinwl

Is there any chance it’s sun or cold damage? I have a young Vanda I got last year with a single patch that looks a lot like the damage on your plant. The patch on mine hasn’t spread and I assumed sun or cold damage had occurred previously.

Definitely possible! Although, this particular orchid is in a tree near other ones. So an interesting case of only 1 being affected like this, and the plant appears to be relatively old too - has definitely been around for a while and probably endured quite a lot during its life.