Struggling with Arrow Bamboo — would appreciate advice

I want to be honest: I'm not getting great results with Arrow Bamboo and I'm not entirely sure why. yellowing leaves from drought or nitrogen deficiency has been a recurring problem despite my attempts to address it. I've been focusing on watering heavily in the first season to establish the root system based on everything I've read.

rapid establishment and fast vertical growth is there in glimpses, which tells me the plant has potential in my conditions. I have it in a focal point specimen in a large container which might not be ideal. new shoot emergence in spring growing at remarkable speed showed some improvement. Two stars for now — not the plant's fault, but not a success yet. I'll update if things improve.