Can you share a photo? What are the camera placements?
* Note: With such dynamic features, the changes in angle can result in not-enough feature matches. You need multiple cameras to "overlap" in their features for them to be accepted. (There's a toolbar button to disable the 3-minimum requirement, giving horrible results on a plant probably.)
1. For 360, you will likely need more photos. You could place the plant on a turntable, and use a plain backdrop to reduce interfering features, then do the shoot multiple times. This can be a problem with a shaking plant. If your fixed-position RPI's could be put on a turning or even unstable setup, it might be another option.
Depending on the plant, many will have many similar features shared (leaves) across angles, and this can cause great confusion in the feature matching process (and low quality results).
2. Another thing you can try is to take the array of photos all from one direction, which will produce a "one-sided" model with much more subtle changes between each viewpoint. Then do the same from another side. The small change in locations might allow a high quality (one-sided sort-of) reproduction which can then be matched up to one taken from one or more other side(s) (most-likely with manual effort and cleanup).