Calla Lilies

Question

When should I plant my Calla Lilies in pots to get them to flower about Mother’s Day?

Answer 1

Plant the bulbs about 2" deep in a well draining potting mix. Water lightly until you began to see the leaves growing. Then you can water to keep the soil moist but not soggy.
Depending on the variety, the temperatures and sunlight, you should see blossoms within 60 to 90 days.

https://www.gardeningknowhow.com/ornamental/bulbs/calla-lily/growing-calla-lilies-and-care-of-calla-lilies.htm