Avoiding crown rot in paphiopedilum

[Grim Tuesday]

I put this paph in semi-hydro about a month ago. It is a pretty small plant, and didn't seem particularly healthy when I put it in S/H as there was only one root that seemed like it was viable. And clearly it was, because the plant is not shriveling up with dehydration. But, last week a leaf at its base dropped off, and now another one is going. I think it's crown rot? Though correct me if I'm wrong. I tried giving it a topical fungicide last week with no effect.

This was surprising to me because I've read paphs tend to enjoy S/H a lot, and can be repotted at any time. Any idea what I could have done wrong? Or was it something that was set into motion before I repotted it? The plant was in a fine bark mix before, and is a henryanum hybrid. I mixed in some grodon grow cubes with the leca for even moisture and also have a layer of rocks on top for stability.

[rbarata]

I don't that is rot...the plat is just sheding older leaves.

[Roberta]

Agree with rbarata... Paphs do shed old leaves - and eventual old growths - as the new ones develop. (Where Phals are monopodial - one growth point, Paphs are sympodial - grow along a rhizome) So where losing leaves like that on a Phal would be concerning, on a Paph it's normal You have a nice new growth coming.

[estación seca]

I agree with rbarata.

Don't move sick plants into S/H. When you do move plants into S/H make sure environmental conditions are good for the plant.

Semihydroponics isn't a rescue method; in fact, it stresses plants for a while. The plant needs to grow a new set of roots adapted to the new environment before it will grow well. If it's already sick it might not be able to do this and you might lose the plant.

Paphs in general do grow well in S/H if the other conditions are appropriate - light, temperature, humidity.

Different fungus are susceptible or resistant to different fungicides. Unless you know which fungus you have and you know it is susceptible to the fungicide you have it isn't a good idea to use a fungicide blindly. You may have no effect on the fungus but you may select for a resistant different fungus.

Growers in homes rarely face fungus issues unless the growing conditions are very far from ideal. Fungus infection is uncommon unless temperatures are far off and humidity is high. Typical infections people may see in homes are Paph. and Phal. crown rot from low temperatures plus water in the crown, and various rots in terrariums with too high temperature and humidity plus inadequate air circulation.

[Paphluvr]

I hate to disagree with everyone, but the lower leaf in the second photo is definitely showing some sort of basal rot that is not normal leaf senescence. Looks like a fungal issue to me. As to what to do, I've never attempted to grow my Paphs in this manner so cannot give you any recommendations other than to treat the fungal issue.

[Ray]

That is not crown rot. It is, as Paphluvr stated, a basal rot, likely caused by the plant being potted too deeply, although if it was a weak plant to start, this may have been inevitable.

I have not found a single Paph that did not do well in S/H (for me, in my conditions), but I have not grown all of them, but S/H is not a “rescue” method.

[Grim Tuesday]

So to be clear, I did not put it in S/H to rescue it. Rather, I thought I would try it in S/H to test if paphs like S/H in my conditions, so I unpotted it, noticed that it only has one root, and instead of putting it back in the conditions that caused it to get to that state, decided to put it in S/H because my leca was all ready to go, and it seemed just as good of an idea as putting it back into bark. Maybe that was the wrong thing to do. I'll also take care not to pot too deeply in the future. Is there anything I can do to treat the basal rot?

[estación seca]

When I started with Paphs I killed some by underwatering. They looked like this. I don't have anywhere near the Paph experience Paphluvr and Ray have, but it's probably been a very long time since they have killed a Paph with underwatering.

If it were rot I would have expected the offset to be dead by now, unless it already had its own roots.

[Ray]

Originally Posted by Grim Tuesday

So to be clear, I did not put it in S/H to rescue it. Rather, I thought I would try it in S/H to test if paphs like S/H in my conditions, so I unpotted it, noticed that it only has one root, and instead of putting it back in the conditions that caused it to get to that state, decided to put it in S/H because my leca was all ready to go, and it seemed just as good of an idea as putting it back into bark. Maybe that was the wrong thing to do. I'll also take care not to pot too deeply in the future. Is there anything I can do to treat the basal rot?

I think that was as reasonable approach as any! Douse it with KelpMax to stimulate growth.