"Hello Lois, QuiltMuses.com here, we want to talk to you about your quilt border"....ah just joking with ya!
Lois, your quilt is so lovely and either the green or the black will work beautifully. Personally I would not agonize over it. Keeping it on your design wall for a few days might help crystalize your own choice.
I have now begun work on my second pineapple quilt. DH liked the first one so much that he wanted me to do another for us. So this time I am going for lights and darks together. Can't wait to see how it works out. I had enough to do 35 purple centres so that is what I am doing.