My old 'Shamus' filled out nicely over 3 years in a small fish aquarium. Then it up and died early this year probably from overwatering. So the growth pattern is a slow one. The leaves also looked like two different plants, the old growth was a dark brown to black color, while the newer leaves were green with dark veining. My new one is in a small (8 inch max diameter) glass bubble (the kind you get at craft stores for less than $5), has leaves up to 3 to 4 inches in length, and is sending roots up out of the soil growing up the glass side (I've seen aerial roots before but usually they come off the stem, not from the soil). Like most rhizomatous types they bloom early spring with small white to pink blooms on tall stalks.

Repotting is a personal matter. Some do it every year, I rarely do it if I like the pot and the way the plant is growing. I usually add soil. If you want a fuller, bigger plant then you have to have a bigger pot but most experts say go up one size when the plant fills the existing pot. You might want to start some more plants instead for a bit of insurance and to give away.

Butch

The small aquarium with 'Chantilly Lace' in the corner, 'Kit Kat' in the back, and 'Shamus' up front. I was able to save 'Kit Kat' and 'Chantilly Lace', but 'Shamus' slowly went downhill. The blooms are okay but can be messy if allowed to drop in the house and that goes for any rhizomatous begonia.

'Shamus' and some other green dwarf begonia (maybe 'Shamus' also has some ordinary green leaves (reversion?)).