dendrobium aphyllum with odd marks on leaves
 

Hello

I was recently given x2 divisions (all new canes ) of a dendrobium aphyllum from a friend. When I received the divsions, the canes were all small and were just sprouting leaves. As the weeks have passed, the divisions have grown.

I was recently looking at the divisions and it appears that some random marks have appeared on the leaves of one of them. It is like they appeared out of the blue. The other division (grown in the same pot) does not have any marks on it. The marks can be seen on the underside of the leaves as well.

The plant is grown under artificial lights in semi hydro however it is a fair distance a way from the lights (one shelf below them and barely getting the full intensity of the lights which are T5s) - my cattleya`s are the closest to the lights.

I am a novice with dendrobiums so would be keen to understand if this looks like a burn or something fungal? I do not spray or allow water to sit on the leaves. I have however recently started using a new fertilizer. As far as I am aware, no insects are present.

Any help most welcome :)

The closeup photo does look fungal to me. I think, just watch it -if it spreads and/or is soft and moist, you could cut out the affected area with a single-edge single use razor blade, dust the cut area with cinnamon. But if the spots don't spread, you are safe leaving them alone.

I agree. The kind of thing I probably wouldn’t have noticed but you are wise to monitor.

It is probably offensive to just say razor blade, because the member is from Switzerland. It should be 'Swiss Army Knife'.

heheh ..... that was a joke only.

It could definitely be fungal. Totally agree.

Petyr ----- putting jokes aside now ..... for your growing area, do you have some air-movement? Some air circulation/air-movement can help cut down or even prevent fungal or bacterial issues.

If you've been using a new fertiliser, and both plants are exposed to the same fertiliser, then it could just mean that the fertiliser isn't the issue here.

Totally agree with D.C. Keep an eye on this one - monitor the situation closely. If you do have some treatments (eg. agri-fos or cleary's 3336 etc), then have it ready - waiting in the wings. Just in case.