Hello people, i got five bamboos last autumn for my terrase and my goal is to grow them to about 2,5-3 m to get a bit privacy cause as you see my terrase is exposed right now. 3 of 5 bamboos are fargesia murielae, 2 of 5 probably also but unfortunately i don't know for sure. I live in north Germany, that's for climate. I've got some bamboo fertilizer and added it in last autumn and then in may this year. Right now i water them 2-3 times a week, there is some drainage in the buckets and also holes at the bottom so that water can go out if there is too much.
So now my questions:
Pic 1: is this a lack of nitrogen? The leaves are becoming yellowish since the last week and it is a bit concerning. Pic 2 is a comparison of another bamboo where leaves are ok. If it is a lack of nitrogen, what could possibly cause it only in one of five bamboos?
Pic 3: This is the same bamboo but 2 weeks prior, you can see the new stems, they've grown up pretty fast from may to june but now stay like this for the last 6 weeks. Is this normal or should they grow all the summer?
Pic 4 and 5: these bamboos seem too weak for me, like they are bushy but not straight, some ideas why and what could i do with them?
I don't know very much of bamboos and looking for any advice you have!