White hairlike fuzz (it's not mealybugs) on den canes

[estación seca]

What have your night temperatures been? This is a hot growing tropical plant.

[KatieM]

Originally Posted by estación seca

What have your night temperatures been? This is a hot growing tropical plant.

60s, dropped last night though but I moved it inside yesterday. He'll stay inside for the winter now.

[Roberta]

Hot? Definitely warm, but I know that mine gets night temps down to 60 deg F or so. And days are whatever the "greenhouse effect" produces, so lately days have been maybe 70 or a bit over but not by a lot. And it grows and blooms for me. I'd think Phalaenopsis temperatures (but more light) would work well. (Mine doesn't get all that much light either because my GH is fairly dark, it seems to do fine)

[tmoney]

howdy....

is the fungus still there?? i didn’t notice this thread before, but if i had i would have chimed in to bang the soap spray drum again. mild soap spray works great for any minor fungal issues we have, especially surface decomposers like you had/have.

perhaps the fungus had dried up now, in which case- great! keep it going!! if not, a couple drops of soap into a small spray bottle and give those canes a good spray down with a thorough flush of the media afterward.

ok, sorry ob, i will stop again with the soap nonsense

[MateoinLosAngeles]

Originally Posted by KatieM

I separated the dead canes, cleaned the good canes up and repotted it and it's already much happier. Sprayed a little peroxide but as y'all suggested I did not spray the physan.

I personally think that Physan is much more harmless and effective as a general disinfectant than peroxide. Drugstore hydrogen peroxide is really damaging to roots.

Have you looked at this Cinnamon DIY spray? Home Remedies › First Rays LLC

I've used it and works well for me for minor things such as those white fuzzies.

Now, your plant is a deciduous plant, which means it will drop its leafs and it's in a resting period. The sheaths are safe to remove if they're dry, it can arguably be recommended.

But I think the main thing here is that if you received a plant in poor condition, then repotted it, then repotted it again, it's just going from stressor to stressor which can really stifle its recovery. Finally, you can do more research on live moss, but being alive the moss will compete with the orchid for resources, further hampering its recovery. And also, won't live moss constantly stay wet or otherwise it will die too? My understanding is that most Dendrobiums will need some sort of dry rest at some point of the year. And I believe yours is one of them. How will you let it dry if the moss is alive? And if it's resting, how is it supposed to adapt to new potting media?

I think you should reconsider the culture of this plant.

[KatieM]

Originally Posted by Roberta

No more peroxide! It can damage roots, especially the new growing ones! If you fix the problems of the medium so that the roots get air, you'll solve the fungal problems without chemicals. (If you have to choose between Physan and peroxide, chose Physan... it may not do much but it's pretty harmless, where peroxide can be very harmful if it gets on roots)

For sure, there are huge differences with different types of Dendrobiums. But that's to be expected - it is a huge genus, Habitats go from humid tropical rainforests to the foothills of the Himalayas and everthing in between so different species have very different needs within the genus. There are different sections within the genus that helps. (To get info about those groupings, do take a look at IOSPE You'll also get a summery of habitat information.

Here is the blurb on Den smilliae
IOSPE PHOTOS

It suggests a "slight" winter rest. I'd hold back on fertilizer, but not water... you water everything less in winter because things don't dry out as fast. (Unless, of course, your growing conditions are hot and super humid like they are in Papua New Guinea lowlands... which they probably aren't)

That's an awesome website I have been on there but I need to take the time to really sit down and dig in especially on the lovely dendrobiums. I had no idea on the peroxide. I've had so many people tell me to use it especially when I get a new orchid to help kill any unknown infections. I will definitely keep that in mind and start experimenting with the physan more. Hopefully I just won't need it but in all things growing there's always something to battle 😉

---------- Post added at 09:03 PM ---------- Previous post was at 08:43 PM ----------

Originally Posted by tmoney

howdy....

is the fungus still there?? i didn’t notice this thread before, but if i had i would have chimed in to bang the soap spray drum again. mild soap spray works great for any minor fungal issues we have, especially surface decomposers like you had/have.

perhaps the fungus had dried up now, in which case- great! keep it going!! if not, a couple drops of soap into a small spray bottle and give those canes a good spray down with a thorough flush of the media afterward.

ok, sorry ob, i will stop again with the soap nonsense

Lol I love the soap mixtures! I used them for pesky mealybugs and works great. Do you have a preference? Would love to hear your favorite. I just starting using a tea tree and mint soap very diluted so it doesn't burn leaves. Has made a night and day difference. Worked better than the rubbing alcohol. Hadn't thought to use it for fungus. Will definitely give it a whirl. I'd much prefer no chemicals if possible. Yes it is all dried up!

[Roberta]

With the fresh medium, you won't have to worry about fungus - you already mentioned that you had removed the bad, rotted growths, potted it up in fresh medium. Now it should be fine. Don't rush to "treat" unless you see a problem. And then any treatment should be tailored to what you are treating. No "shotgun" stuff.

[KatieM]

Originally Posted by MateoinLosAngeles

I personally think that Physan is much more harmless and effective as a general disinfectant than peroxide. Drugstore hydrogen peroxide is really damaging to roots.

Have you looked at this Cinnamon DIY spray? Home Remedies › First Rays LLC

I've used it and works well for me for minor things such as those white fuzzies.

Now, your plant is a deciduous plant, which means it will drop its leafs and it's in a resting period. The sheaths are safe to remove if they're dry, it can arguably be recommended.

But I think the main thing here is that if you received a plant in poor condition, then repotted it, then repotted it again, it's just going from stressor to stressor which can really stifle its recovery. Finally, you can do more research on live moss, but being alive the moss will compete with the orchid for resources, further hampering its recovery. And also, won't live moss constantly stay wet or otherwise it will die too? My understanding is that most Dendrobiums will need some sort of dry rest at some point of the year. And I believe yours is one of them. How will you let it dry if the moss is alive? And if it's resting, how is it supposed to adapt to new potting media?

I think you should reconsider the culture of this plant.

I am super intrigued in the cinnamon mixture. I will absolutely be doing this. Thank you very much! These are all very interesting points to consider. I've done several experiments with live Moss over the years. You have to leave it very loose so that the plants can still get the air circulation. You only mist the top occasionally actually less often than I need to water a normal bark mixture to keep it alive. It has saved some rescue phals the people have given me including rootless and crown rot but to your point it may not be for this type of orchid particularly because it's a dendrobium. Yes I am thinking more and more peeling off the sheaths is a good thing. I did do that and it seems much happier. Yess good point on the repotting twice. I was afraid the mix was infected. I'll keep y'all posted on what works and what doesn't. Thanks again for all of the feedback and advice!

---------- Post added at 09:22 PM ---------- Previous post was at 09:21 PM ----------

Originally Posted by Roberta

With the fresh medium, you won't have to worry about fungus - you already mentioned that you had removed the bad, rotted growths, potted it up in fresh medium. Now it should be fine. Don't rush to "treat" unless you see a problem. And then any treatment should be tailored to what you are treating. No "shotgun" stuff.

Well said. Just needs to rest and recover.

[Roberta]

Just for reference... here is my Den smilliae from this year (bloomed in October) Note that it is blooming on leafless canes. But the whole plant isn't deciduous... the newer cane in the first photo (from this year) has its leaves. Over the next months, as newer canes emerge, it'll lose leaves. But it's not seasonally deciduous. And the older, leafless canes can bloom more than one year, especially as the plant matures. I had it for several years before it got big enough to bloom - blooming-size canes are 12 to 15 inches. So be patient. It is a really lovely species.

[KatieM]

Originally Posted by Roberta

Just for reference... here is my Den smilliae from this year (bloomed in October) Note that it is blooming on leafless canes. But the whole plant isn't deciduous... the newer cane in the first photo (from this year) has its leaves. Over the next months, as newer canes emerge, it'll lose leaves. But it's not seasonally deciduous. And the older, leafless canes can bloom more than one year, especially as the plant matures. I had it for several years before it got big enough to bloom - blooming-size canes are 12 to 15 inches. So be patient. It is a really lovely species.

That's stunning! I have a couple others that are more of a semi deciduous like you are describing so this is great to know. Will definitely not be cutting any canes. This will be worth the wait! So much fun learning about new types of orchids. They are like children, related but oh so different and with so many different needs.