Sorry if this is the wrong forum but I recently got into sinnigias, I have a love for all things caudex, and have noticed two of my ones have been developing brown spots on their leaves.
What's is this? Is it water or bugs or something else?
My collection is in an east facing position that is sunny for about 4 hours in the morning.

Hi Jim,

The closest plants I have related to your question are some African Violets and a Streptocarpus that came as a stow-away with an orchid. The Streptocarpus apparently doesn't even need soil as it has been growing in a bowl of water for several years now. But none have ever shown any inclination towards a caudex.

You might want to ask for a transfer to the Ask a Question Forum:
https://garden.org/forums/view...

or the African Violet and Gesneriads Forum:
https://garden.org/forums/view...

The link to transfer is just below this text box in bold "Suggest a Change"

Thank you Daisy, I have posted to Ask a Question as I couldn't see the option to transfer it there.
They're cousins to African Violets but don't seem too much like it, I don't have much experience with AV though.

That happens on some of the Achimenes I grow and to the hybrids between them and closely related species. It occurs, but much less so, on the Eucodonias. I used to think it was sun hitting wet leaves, but it hasn't been consistant enough for that to be the sole cause. Somehow I do think it is associated with wet foliage, but I haven't been able to nail down a specific cause resulting the effect seen. Some Achimenes are more prone to it than others. It's also seen more in the latter parts of the growing season than when they are waking up in the early part of the growing season (all the gesneriads I'm growing are rhizomatous and go dormant in the winter months). Someone on the Gesneriad forum might be able to have an answer.

It could be water on leaves but wet leaves doesnt seem to worry 2-3 of the other sinnigia's I have but then again that falls in line with what you said. I'll request a move but I might also just stop lazy watering it with a can and water it carefully.