Structure of plant leaf
 

If I remember my rudimentary (almost extinct now) school level Botany as a student of Biology, a plant leaf is supposed to have a dorsal surface and ventral surface, ventral is for photosynthesis and dorsal is for gas exchange much like human lungs.
Much is talked about keeping the ventrals clean with the help of moist facial tissues to soft cloth and dilute lime juice and some chemical ( name I don’t know) to keep the leaves shining , the latter view I don’t subscribe because shiny leaves are inherent.
My point is , what about the dorsal surface which is extremely important and also can serve as a nidus for infections and infestations? Can the surface be cleaned with moist facial tissue ?

Ravi - all depends on the plant I think. Epiphytes have evolved differently than terrestrial plants like cymbidiums, Disa, Paphs and Phrags.

Gas exchange is happening on almost all the orchid roots too - which is why the hobby is always yammering on about some latest media craze (Orchiata - is it really better?)

Air movement, humidity, misting and watering should be enough to clean the leaf and root surfaces to improve gas exchange. You shouldn't need to be cleaning your leaves unless you are growing orchids in a construction zone.

If you are talking about cleaning pests / infections from leaf surfaces... better air movement works best for fungus in my experience. Isopropyl alcohol at 50% strength (and a bit of dish soap) has been effective in battling scale for me (at least somewhat - as good as insect soaps i've tried).

Keep in mind that large industrial cities in places like the United States, India, China, etc. can have pretty severe air pollution problems, including particulates that you may want to wash off.

If it is just cleaning you want to do, a dilute, mild dish detergent solution works well. To avoid spreading disease between plants, apply the solution with a sprayer, wipe dirt off of each individual plant with a new paper towel that is discarded before moving to the next plant. I rinse plants thoroughly after the soap solution.

If your leaves don't appear dirty, the leaf cleaning may not be necessary (after all, nobody cleans the wild orchids!!)

Thank you very much for sharing your experiences

I wipe down all the leaves with a damp paper towel once in a long while (less than once a year) to get rid of accumulated dust (and pollution, back when I lived in a city), or chunk them in the bathtub and shower them clean. My plants are never outside so never get rain to clean them off. I consider leaf cleaning to be very low in the list of things to do to keep the plants happy and healthy...


About Orchiata, it is better mostly for plants that stay damp between waterings (like Paphs/Phrags) since the bark doesn't break down so fast, and stays optimal for a much longer period. Other than that, I don't see why else you'd use it over other types of bark.