The best time to fertilize your Calla Lilies is during spring and summer, while the plants are actively growing. However, you may also want to fertilize your new Calla Lilies at planting to give them a boost right from the start. So, when their growing season starts in spring, apply fertilizer according to the package directions.

Calla lily fertilization should also be done at planting. Feeding calla lily plants at planting and again each spring can help promote huge blooms with more flower production. Avoid high nitrogen feeds that will encourage foliar development but reduces flowers.

Calla lilies need feeding upon planting, and again every spring at the beginning of their growing season, in order to promote bountiful flowering. Most well-balanced fertilizers will work just fine, but avoid choosing a blend with too much nitrogen, which can reduce the plant's flowering.