Available in a range of colors, calla lilies (Zantedeschia) bloom in the summer for one month. While they grow widely, they need frost protection in some climates. You can eventually produce more calla lilies by dividing the plant rhizome, but cutting flower stalks won’t produce more flowers.
Some lily plants grow more flowers if you deadhead the plant by removing old, withered flowers. Asiatic and Oriental lilies in particular continue to grow when you pluck off the spent blooms. With Asiatic and Oriental lilies, you don’t need to cut the stem back to bear more flowers; this actually produces the opposite effect. While deadheading is a similar practice, it doesn’t involve cutting the stem of the flower, just removing the flower.
Calla lilies are not a true lily, like the Asiatic and Oriental lilies that benefit from deadheading. Thus practices that benefit members of the lily family might not benefit calla lilies. There is no evidence to suggest that calla lilies grow more flowers if the stems are cut down.
Calla lilies grow well in garden beds, in container gardens and as houseplants. These flowers are container hardy in United States Department of Agriculture zones 2 to 8, where they can be moved indoors for the winter, or the bulbs can be dug up for winter if the plants are planted in the ground. They are hardy year-round in zones 9 to 11. The bulbs get injured at 25 degrees Fahrenheit. Calla lilies make excellent cut flowers, according to North Carolina State University horticulturist Erv Evans. Cutting doesn’t benefit the plant, but it does give you a bouquet.
While calla lilies don’t grow more flowers on the stalk from deadheading, you will need to remove spent flower blooms for aesthetic reasons. Since the stalks won’t bear more flowers once they bloom, cut spent flower stalks down at the base.