Seed lists, traditionally called Index Semina, allow gardens to select species carefully. Staff review what is legally permitted, climatically suitable and aligned with garden development goals before requesting anything. This process helps prevent inappropriate or potentially invasive introductions.
Unlike commercial seed sales, botanic garden exchange is non-profit and different in purpose. Seeds are shared for scientific study, conservation collections and public display - not for trade.
Many of the species listed are not commercially popular, and often not easily available. Through seed exchange, gardens may obtain seed identified and documented in the plant’s country of origin, sometimes even from known wild collections. This helps give stronger provenance records and, where possible, broader genetic representation.
Responsible gardens pay close attention to provenance because origin influences how plants grow and how they should be managed.
Participating gardens operate under their own national laws and biosecurity requirements. In New Zealand, that means strict safeguards around what can be imported or grown. International agreements such as the Nagoya Protocol also guide ethical sharing of plant material. Seed exchange is built on trust, documentation and respect for origin.
Like zoos, botanic gardens hold living collections in trust for the public. Seed exchange is one way they strengthen those collections responsibly — sharing knowledge as well as plants. From a small packet of seed can grow not just a new plant, but a collaboration that spans continents, linking local landscapes to a wider global effort to safeguard plant diversity for future generations.
In the Dunedin Botanic Garden, living collections like the Geographic Plant Collection, Rock Garden and Winter Garden have evolved and flourished through participation in seed exchange.
