Quality Issue Reject

This is a very standard image of a garden shrub taken when I was looking for something to do on a dull winter day. Rejected with quality issues as a reason. I contribute to a number of other stock  with few rejections. This particular image has been accepted elsewhere. I confess to having a hit and miss approach and would like to be a bit more savvy technically. One didadvantage I have is that I am colour blind Please give me your feedback. I know the subject is not particularly interesting but help regarding the technical issues would be appreciated.