Open-pollinated means insects or wind (or far less frequently other animals or natural mechanisms) transport pollen between individual plants. This unrestricted flow of pollen results in the greatest genetic diversity and variation within plant populations.
Biological diversity allows plants to incrementally adapt to the growing conditions of specific locations. For open-pollinated plants to remain true-to-type it is critical to isolate plant varieties that can cross pollinate.
Photo by Bill Durrence © 2018