Q.How do you know how much to water or fertilize a Calla Lily?
How much nitrogen do Calla Lilies need in their potting soil?
I transplanted my Calla Lily fearing it had rot. I disinfected the unglazed pot, put in drainage material and fresh rapid gro planting soil.
The next day my plant is dropping. Help me save my lily please.
They do not need super rich soil to survive. Too much nitrogen will cause this. It could still be an issue of root rot, though. They need slightly moist soil, and can tolerate a slight dry period, but they prefer moist soil. They will not want wet soil though. This will cause rot. I would add peroxide at 1/3 peroxide to 2/3 water the next time you water to be sure that you kill off anything in the root zone.
They can also suffer if they are in full shade. They like bright, but indirect light, but can handle full sun as long as it is not too hot.
Here is an article for more information on their care: https://www.gardeningknowhow.com/ornamental/bulbs/calla-lily/growing-calla-lilies-and-care-of-calla-lilies.htm