Hello everyone!
I have two orchids that I grow in a mini greenhouse on a southeast-facing window. They had spider mites, and I was treating them with a miticide that contains canola oil. Everything seemed fine for the past few months, but since it’s winter, there has been very little sun.
If you notice any bugs on the leaves, I released predatory mites about three weeks ago. Before that, I washed the leaves to remove any remaining miticide. Over the past few weeks, it has been sunny almost every day, and temperatures on the window where they sit have reached around 32°C. It is verry difficult to completely wash off the miticide because of the oil. The sun is quite low this time of year and reaches inside the room - usually, it’s blocked by the balcony above, but with the UV filter installed, it still feels very intense.
I’m wondering if the heat and sun, combined with any oil residue, might have caused the leaf damage. Another possibility is a nutrient issue - I've been growing them in semi-hydro for two years, but while washing and reapplying the miticide, I forgot to add fertilizer.
I’d really appreciate any insights! Thank you so much for your help, and stay safe.
P.S. The last photo with one leaf is the second orchid.
Heat damage, nutrient deficiency or something else?
Linear Mode
