Dendrobium cuthbertsonii hybrids and leaf falljng

[clintonsparsons]

The plants I ordered looked great when I got them 3-4 weeks ago. I mounted them with some live sphagnum and ever since I received them they have done nothing but drop leaves. I water once per day with RO water only. I havnt fertilized yet. I completely soak the moss pad when I water and by the next morning the moss pad has dried some, but it's still moist. . The moisture level before watering is similar to a well wrung-out kitchen sponge . Humidity is 85-90 %. Nights are 48-53, days never above 75. Air flow is more than sufficient, as is light.

Is it just shock from being mounted? The canes are firm. Am I just being impatient? I am new to orchids. Also, when I say I saturate the moss pad, I meann like three sprays fr ok m a mister bottle is enough to saturate it.

20200814_195227 by Clint Parsons, on Flickr

20200814_195207 by Clint Parsons, on Flickr

[estación seca]

Were they red like that when you got them? And I don't think you're watering enough. Have a read here about how a commercial grower takes care of them:

Alan Koch, Gold Country Orchids, DVOS 2017 02 16

[clintonsparsons]

I have read everything I could before I bought them, including the linked page. They were green when I got them, but I have very high light. I am in the slow process of titrating the light down.

I grow mostly nepenthes and heliamphora. I got these orchids as companion plants.

I will move to watering them twice daily instead of once daily..

[Roberta]

Along with drying out too much, getting the light level down is another factor... depending on what it's hybridized with, Den. cuthbertsonii itself likes fairly low light. My success rate with Den. cuthbersonii isn't great, but so far I'm keeping them alive - mounted, but I put the mounts into terracotta pots with some sphagnum. My challenge is heat - the terracotta helps keep roots a bit cooler. But hybrids tend to be a bit more forgiving.

[clintonsparsons]

One is an illusion, the other mtn butterfly kisses or something like that.

Temperatures arent a problem since I grow in a fridge. I figured the plant would eventually adapt to the high light, but I will turn it down more.

My mount is actually made of clay. Here is my fridge 20200815_110340 by Clint Parsons, on Flickr

I am growing them on mounts to take advantage of the vertical space. Maybe I should just add more sphagnum and water once daily like I already to? I would amount them and put in a pot of live moss, but dont want to stress them.

Can I cut off a couple of canes to try and root in live moss? Then I would have a backup. Or would that just stress it out?

---------- Post added at 06:07 PM ---------- Previous post was at 05:57 PM ----------

I guess my problem is that words like "wet" "moist:" and "dry" are very vague and totally subjective. Doesnt tell me much of anything.

[Roberta]

Your setup is so different from my outdoor area, it is hard to make comparisons. Your 'fridge is probably quite humid, so humidity is probably not an issue either. With that setup, Den cuthbertsonii probably does not want or need extra moss. Question... since these are hybrids, what else is in there? I have a friend with outdoor conditions similar to mine, who has given up on Den. cuthbertsonii but has had good luck with a hybrid of (Den cuthbertsonii x Den glomeratum) x Den cuthbertsonii, so 3/4 D. cuthbertsonii. It looks a lot like cuthbertsonii, but larger - and a lot more heat-tolerant. So if you have one of those, or something else in the hybrid mix that is warm-growing it might actually be too cool. Your setup looks like it may be ideal for the species.

[clintonsparsons]

One is a hybrid with glomeratum, the other lewesii. I hadn't considered that it could be too cold! My pure cuthbertsonii was acquired at the same time, except it came mounted with NO moss. It has only lost 1 leaf since I got it. It is working on a couple new roots.

[Roberta]

I think that it might, indeed, be too cold for the hybrids (which were made with warmer-growing species precisely to make "cuthbert lookalikes" that are easier to grow.) The pure species is probably quite happy bare root with the chilly humidity, which is a lot like "home".

[estación seca]

There are very few small mounted orchids that will tolerate growing above pitcher plants that are getting sufficient light. That is far too bright for those orchids.

[clintonsparsons]

Sounds like I should give them away before they kick the bucket

I will water more, move them as far down as I can, dim the light a little more and hope for the best. Either my experimenting will work before they die or I will just give them to someone for free.