I received one virgins bower plant several years ago from a friend. It is growing WELL and flowers, but I never get any seed heads. I have taken cuttings which are growing into mature plants, but still no seed heads on any of the plants. I understand that plants probably need cross-fertilization and maybe can't get it from a "cloned" offspring.. https://www.minnesotawildflowers.info/shrub/virgins-bower How can I assure that if I purchase another plant it would be a candidate for cross-fertilization? Thank you for your response.