Black spots & loss of all NEW growth on zygo

[Viia]

Apologizes in advance for the long post, but I could really use some help with my zygo. I have had this plant for about a year and a half now. It has never flowered and all the new leaves get brown spots and slowly fall off. The older bulbs and leaves that were mature when I bought the plant are in the same condition they were when I bought it. The new bulb it grew after I bought it is now bare after all the leaves developed brown spots that spread. The newest growth also has brown spots. There is new growth coming from the 1st leafy old bulb.

The photo is a bit old, but you can see how the brown spreads and then the leaf yellows. The yellowing leaves have all dropped since the photo and the new growth at the front is bigger but spotted (it basically comes out with spots).

It's in a medium light position on a bookshelf across from a north-facing window. I haven't repotted since I got it so I guess I should do that soon. The bottom is rocks and the roots are gray but solid looking. There has been no new root growth at the bottom. The top of the pot is coconut husk. I hadn't seen any root growth there until recently.

I used to dip into filtered water and then soak the pot for 10 mins once a week using leaf growth orchid fertilizer at recommended amounts 3 times a month (once a month was a flush watering). My mother (who manages to get the same exact type of plant to produce over 20 flowers at one time) uses the 10 minute soak method, but she says nurseries actually don't water, they just spray from the top. So lately I have started dipping it in filtered water and then dipping in fertilizer for a minute. I also spray the top of the substrate/roots of all orchids every day (it can get pretty dry in the South African summers). I can see that there is now new root growth at the top of the substrate. The bottom of the pot is fairly dry before watering.

So what do you think the issue is? Disease? Low humidity? Too much fertilizer? Too much water? Too little water?

[Brotherly Monkey]

I don't have much experience with zygos, but a zygo hybrid I have does that when it's not being kept moist enough

[nutgirl]

I've had similar problems with my zygo.

I found some interesting info in a recent post from Camille1585 - Help, my Zygo is rotting

From the comments I think I was stressing mine with a poor repotting choice and not the right watering.

Mine lost most of it's roots and leaves (yellow and lots of black spots). I revived it using water culture and have recently potted it. So far so good. Continued new growth and no spots.

I've made it my one goal to successfully grow one of these things.

Maureen

[zxyqu]

I've grown several Zygo's, and without a newer picture I can't be for sure. But, most that I've cared for hate to get any water on the leaves for long periods, and black spots notoriously appear if it sits for too long. I'm not sure that is the case here. Another guess I would have is it might be a hybrid that doesn't like to keep it's leaves. I have no idea why, but my Agx Eva's Blue Amazon, will flower and then all of the bulb's leaves will slowly die off as a new growth takes up the torch. Could You post some more pictures so we could get a better idea?

[silken]

do you know the name of your zygo? I have a tiny Z. mackayi which looks healthy but sure is slow. OrchidWiz says zygo's in general should never dry out and should have lots of water during the growing season, but somewhat less in winter. High humidity of 80% is recommended and high light although not direct sun, which could burn. It sounds like yours could maybe use more light and possibly more water. It said if they fail to bloom, it is usually not enough light.

[King_of_orchid_growing:)]

Old leaves die back after a while. The old leaves that the pseudobulb emerge from always dies back after the pseudobulb matures. The youngest leaves on the top of the pseudobulbs are the ones that last the longest.

If the leaves are getting sprayed, I would recommend against spraying them.

Grow drier during the winter.

Spring and summer is growing season. Winter is when they slow their growth way down.

[Viia]

It's a Kiwi Choice x Arthur Elle. I never spray the leaves so that shouldn't be the cause of the black spots.

I will get a recent photo and post that up soon. The thing the worries me is that it's not shedding leaves on old bulbs. It's shedding leaves on the newest bulbs, and all of them. The old bulbs still have the same leaves they had when I bought the plant over a year ago.

The black spots seem to be indented, like the cell tissue has collapsed in. Maybe it's a micro nutrient that's deficient that's required for new leaf production?

[silken]

The new pb's losing leaves before the old has me stumped! Have you looked at the roots of one of the newer pb's that lost leaves?

How do the leafless newer pb's look? Are they still green and plump? Maybe they are getting a bacterial rot from being too damp when they are young and tender. Just throwing out thoughts here.

[Viia]

The newest growth doesn't have any roots at all (not even rotten or dried ones), but it hasn't formed into a bulb yet. The leafless newer bulb is still pretty plump and healthy looking except for all the dried brown leaf remnants around it. The plant is putting out new roots from the still leafy bulb just before the newer leafless.

I doubt it's rot as the pot does get pretty dry before watering. If anything my worry would be under-watering.

[silken]

I would try increasing watering then as OrchidWiz does say they shouldn't completely dry out when actively growing. And no direct sun. Maybe new tender leaves are too tender for real high light. Keep us posted.