Swarm Breeding

AKA mass selection

Massive planting of seed, followed by selection and planting of the next generation - also as a large number. This allows cross-polinization and eventual retention of desired properties. This is simply mass selection - and is how plant breeding happenned over milennia prior to genetic engineering and cloning. Cloning involves the selection of a single 'nice' variety - and cloning it - while if cross-fertilized - it would not revert to 'less desirable' properties. This is a concept pioneered by Luther Burbank - see mass selection - https://en.wikipedia.org/wiki/Luther_Burbank#Mass_selection - for a distinction from classical breeding.

Classical breeding is essentially selecting few elite individuals and crossing them, whereas swarm breeding (mass selection) means working with large populations, letting desirable properties emerge with succeeding generations. Then propagating the select good candidates, in mass numbers, and in a large number of generations (more than 2 or 3).