Cymbidium with black leaves
 

Hi all.
about 6 month ago I purchased a cymbidium and when it arrived it was not in good shape. the tip of the leaves kept getting black like it was burnt and I kept cutting the tips.
another problem was the poor condition of the pot medium which forced me to do a repot and it turned out that all of the roots were rotten.

I repotted the plant in semi-hydro to encourage root growth since i had good luck using this method with a phal. but the plant's condition keeps getting worse. after a while the mealy bugs appeared which I tried to contain them with a solution of alcohol-water-soup and now the base of the leaves are turning black.

I attached two photos of the plant in order to give you a better idea of the situation

is there anyone who know what is wrong with this plant or what am I doing wrong ?

https://imgur.com/aCbcQhd
https://imgur.com/aCbcQhd

Welcome to the Orchid Board!

It is a difficult situation, and you are doing your best. The older growth is probably dying. If the newest growth has begun making roots, it has an excellent chance of surviving. My experience has been cymbidiums do well in semi-hydroponics.

What are your temperatures? What light is it getting? How often are you watering it?

The initial leaf-tip blackening was likely from old, residue laden potting medium and root damage. As ES stated, once new growth with new roots get going, it should be fine.

I believe it will survive. To speed up the recovery and have a better grow, use a smaller pot.

thank you everyone for your help, it is much appreciated!

the temperature is around 20-24 C almost all the time.
as for the light the plant is sitting about 1 meter away from a south-east window, receiving direct sun light in the morning for about 2 hour (because of the winter time and weaker sun rays of course) and then bright/medium light for the remaining of the day.
I mist the surface of the lecca almost every day since i am in a fairly dry climate, the humidity is between 20-40 % in the room the plant is and i have placed the the plant in a tray of water to help with humidity. apart from that i flush the pot almost every week or two and water when the reservoir is below 20% capacity.

the problem is that i am not seeing any new growth or new roots... :(

You aren't watering enough. Plants in S/H should have a thorough flush at every watering. They grow better the more often you water. I would definitely flush this plant in S/H at least once a day. You do not want the new roots to become dry. Once it is growing strongly and rooting, you may cut back on the frequency if you like. But especially in a lower humidity climate, more frequent flushing will lead to better growth.

ok, I'm gonna start flushing much more frequently, but the reason that i was not watering/flushing a lot was the mealy bugs . i was afraid that all the moisture would just result in an explosion of mealy bugs...you know, out of the frying pan and into the fire kinda situation.
any suggestion on that?

Mealy bugs aren't affected by watering. They can be killed by spraying with 70% isopropyl or ethyl alcohol, or with liquid dish soap diluted 5ml in 1 liter of water. This does not kill eggs so it must be repeated. Various insecticides kill mealybugs.

If that is a standard pot you’re using with LECA, put it in a tray of water to keep it moist. Still follow ES’ advice about heavily watering. Ideally, you don’t want the LECA to ever be dry.

I don't know which Cymbidium is yours (if you have a tag with a name, please post it) but a constanat temp in that range might prevent it from blooming.