Rub the side of each seed near its point with fine-grit sandpaper until the top seed coat is nicked but the inner seed remains undamaged. Scarifying the seed speeds up germination, especially for luffa gourd varieties.
Soak the seeds in a bowl of tap water for 24 hours. Soaking further softens the outer seed coat and encourages water intake so the seeds germinate better.
Sow the seeds immediately after soaking them. Plant the seeds in biodegradable pots indoors for later transplantation or sow them directly into a well-drained, full-sun garden bed after frost danger has passed. The planting depth varies, depending on the gourd variety, but 1 to 2 inches in depth is generally recommended.