Replacing the stock every year probably makes the most sense. I did a quick search on the googler to see if there is a specific reason why you might not be getting flowers:
https://www.youtube.com/watch?v=1-QKEeQQEyMIt is one data point, but the short story is, it won't bloom in high nutrient environments. It must need some stress to feel the need to pollinate and sexually reproduce, otherwise, maybe it is content in high nutrient environments to just clone and make as much vegetation as possible, going crazy and neglecting bloom until it feels the need to go dormant.
If you're using them to strip nutrients from your BOW, you will likely not ever see them bloom, or if you do, it may be time to take them out!
Your setup is still visually appealing, even without the flowers. I think the symmetry around the dock and the geometric shape of the corral makes it look ornamental and aesthetic.
@Snipe. That may correlate with the difference in growth rates you're seeing. You may get less vegetation, and therefore be more likely to bloom. I would assume that a bloom would correspond with seed production, maybe?
