This is a new Begonia species to the hobby, still unidentified to my knowledge, from West Kalimantan in Borneo. It was assigned the U number 682 in 2021 and was previously identified as ‘sp. Kapaus Hulu’. Here is the plant newly propagated via leaf cutting, growing in sphagnum.
Update this Begonia is turning out to be a real stunner! After switching it out of sphag and into a soil mix, it has tripled in size in about two months and is about to flower. I talk about sphagnum conspiracy here, involving nutritional deficiencies with Begonias kept on sphagnum long term. It is not a new theory, but one that seems to be often forgotten as it seems to be an issue that depending on the species can go on for years before becoming problematic. In the Bornean species, they do not wait that long and after a few months without fertilizer on sphag they crash in my experience. I think of them like hummingbirds and bats- they do not have a lot of stores and so need to eat constantly in very small doses. Below is a plant that was repotted about 4 months ago into soil, looking very robust now.
And a picture taken with the flash (kind of obnoxious but you can see the color better)
The female flower,
The plant below is the same species but was only recently transferred out of sphagnum to a soil mix. You can see the old growth is yellow/red, and not very robust. The new growth is looking better. It has been off sphag for around one month.
This plant (below) has been off sphag for 2-3 months.
Soooo, no more sphagnum for this one! 🙂