Tiny Black spots on leaves

[orchidlauren]

Hello, my orchids have had tiny black dots on the undersides of their leafs, but I’m just now wondering what they could be, they currently don’t have any pests (with good inspection) And i’m wondering what the cause may be? All of my orchids are thriving and just been repotted.

[estación seca]

Hi Lauren! A Phalaenopsis, right? It's hard to say what caused those. We almost never have fungus issues here when growing on a windowsill because the humidity is low. I would just watch the plant. If it seems healthy otherwise, don't worry about it too much.

I may have mentioned this before - the Desert Valley Orchid Society is in Phoenix. We're meeting entirely via Zoom. You might be interested in joining and attending some of the meetings. Your parents could contact the Society officers with questions at the E-mail address on the Web site.

[orchidlauren]

Phal indeed, Its growing well and actually had a keiki that has these dots too. I, suprisingly think it might be a fungus because the newer leaves have little/none of these dots, if thats the case, does fungicide work? And thank you for the suggestion!! I’ll check it out and join if I can!

[estación seca]

Not all fungi harm plants. Some are beneficial, preventing the growth of harmful fungi.

Not all spots are fungi, and not all fungi on plants are causing damage. Some fungi only feed on already dead plant tissue. These are called saporophytes. They don't harm living plants. They generally look like strands of cotton wool.

Not all fungicides kill all fungi. Some fungi may be resistant to some fungicides. So before you use a fungicide you should have an idea of what fungus your have, and whether it is susceptible to the fungicide you plan to use.

Fungicide also kills beneficial fungi. This may actually make things worse for a plant. So I don't use fungicide unless I know:

• Fungus is harming my plant;
• I know what the fungus is;
• I know the fungicide I have kills that fungus.