wisteria all caged in

Can you explain why you do this?

hi drc , did xplain on the other photo lol, i got this last year and it was half way up the post. then my new pup desided it wud b gud fun 2 chew it all of .i was not happy bt it. so i triedto revive it by putting gud muck round it and putting a bottle over it . thort it had died. but it come bk so am happy now. but keeping the cage on now lol xx

thanks