My bonsai tree's leaves turned brown but didn't drop in the run up to autumn last year. We are careful about over-watering, so assumed this was a seasonal thing (although it hadn't done it the previous year). As such, we've been patiently watering it and expecting it to come back in the spring. However, spring has passed and still nothing. "It's likely dead" I hear you say, well that's what I was starting to think so I shaved the trunk and branches in a few places again today (I have done this every few months), and the cambium layer is still green.
What do I need to do to convince it to re-leaf? Just have more patience? I'm really rather baffled... Just my luck to be the proud owner of a permanently leafless bonsai!