This is a Begonia collected in Julau, a small town in Sarawak (Borneo). In 2021 it was given the U number 684 and was previously circulated as sp. Julau narrow form. It is a taller species that is prone to falling over when it reaches a certain height (the magic number for my largest plant is 14″), with only a thin stem to support the top-heavy plant. I’ve only had it about six months so cannot say too much about its growth but will share my observations from this time. Out of the many leaf cuttings taken, none have rooted. Potting mediums include sphagnum, potting mix, perlite, and clay mixes. They never root but just rot and shrivel up in short order. Since it is so top-heavy, I’ve been trimming it when it starts to flop and the cuttings have all taken. They have been 2-3 inches with 3-5 leaves and rooted in sphagnum. As it’s grown the leaves have gotten larger, around 2-2.5 inches long at the largest, and the pink markings between lateral veins have become more pronounced.
There are at least two species or clones of ‘Begonia sp. Julau’ circulating. The one pictured here is the narrower type but there is another that looks similar but distinctly different with much wider foliage and more pink coloration. Recently I saw that Avery Orchids had the wider leaved form labeled as Begonia amidalae.
Update,
this species produces the most incredible flowers! I did not even notice flowers forming and opened up the bin one day to these fully formed ovaries. I think it must be in section Petermannia, due to the females coming out well in advance of the males.
