Question
I live in southern California and I have three very large, white, calla lilies. They are doing too well! They look beautiful but I have a small yard and they are getting too big. How and when do I need to prune/cut these back? Thank you.

Answer
Hi Rachel,
Thanx for your question.  Is your calla bed getting bigger?  The large white callas are Zantedeschia aethiopica and they get quite large.  You can separate them when they go dormant in the fall and winter.  Just dig them up, shake off the dirt and separate the rhizomes.  It sounds to me like the callas have increased and have become crowded and unkempt.  When digging up the rhizomes be sure to give them to other gardeners as this is a prized plant.  I hope this helps and if I didn't understand your question let me know.  Generally, one does not cut back or prune calla lilies.  What happens is that year after year, the planting gets bigger and bigger as the roots/rhimzomes multiply.  Accordingly, one digs up the planting and thins out the rhizomes.

Tom