Q.calla lilies questions
My calla lily plants don’t come up until April. Is that later than it should be? By the time they bloom, it’s too hot to keep them blooming. What kind of fertilizer should I use for my calla lilies? How soon should I start the fertilizer?
There are literally hundreds of varieties of calla lily, that bloom from spring through fall, in a range of climates. The kind you're using may not be ideally suited for your climate. You can check with the count extension service for the names of varieties you might want to try. This link will help you locate one. https://www.gardeningknowhow.com/garden-how-to/info/what-is-extension-service.htm
These articles might also give you some more basic information: