How to Fertilize saucer plant?
Apply a dilute cactus/succulent fertilizer twice during the active growing season.

saucer plant · Aeonium undulatum
Grow under glass in a standard cactus compost, in full light. When in growth water freely and feed every two or three weeks with a low nitrogen liquid feed. Keep almost dry in the winter. See houseplant cacti and succulent cultivation for further advice
Apply a dilute cactus/succulent fertilizer twice during the active growing season.