The Leaves on My Calla Lily Plants Are Turning Yellow

Answer 1

Calla lily plants are best grown outside. If grown indoors, they require very high light, and will need proper fertilization. Since you didn't say how old the plants are, they may be trying to be dormant. Almost all bulbs need a period of dormancy. Hopefully the article accessable by this link can answer your questions: https://www.gardeningknowhow.com/ornamental/bulbs/calla-lily/growing-calla-lilies-and-care-of-calla-lilies.htm
If you need more information, enter the word calla in the search window, and you will access links to other articles covering callas.