A 24-step protocol outlining the creation of mixed gametophyte cultures from kelp sorus tissue. Details precise methodology for sorus release, spore counting using hemocytometers, and culture management. Includes specific guidance on media preparation with F/2, kanamycin, and GeO2, along with critical timing for dark period, light transitions, and water changes. Features calculation methods for optimal spore density and container allocation. Essential reference for nursery technicians establishing and maintaining kelp gametophyte cultures for successful propagation cycles.