Dividingcallalilies is not difficult. Lift calla rhizomes in fall after the foliage turns brown and pulls away from the roots easily. Slide a shovel under the roots and pry upward to lift the clump. Callalilies multiply very fast. You need to thin them down every 2 to 3 years otherwise they will not bloom well. Can I divide my Callalily?According to Sunset Western Garden Book (2007), Callalily ( Zantedeschia ) should only be divided if it shows signs of decline. Learn how to effectively dividecallalily bulbs for thriving plants. How to Divide & Pot CallaLilies & Other Rhizome Plants. Rhizomes are plant bulbs that are flat in shape and very bulbous in size, a typical example of a rhizome is ginger. A thread in the Beginner Gardening forum, titled DividingCallalilies.I got several rhizomes of 'Pink Giant' callalilly (Zantedeschia) a few years ago and they have done very well for me. I believe these are CallaLily's. I am not sure. The previous homeowner did not say. But there is a huge mass of them. I love them, they are so tropical and s… When to DivideCallas Most growers prefer to dividecallalilies in spring, especially in warm climates where you can leave the rhizome in the ground year round. CallaLilies are divided during the winter months whenever it's necessary, so there is no set timetable. The clumps are dug up and segmented into smaller sections, and replanted. Impact of avoiding Calladivision. If you don't dividecallalilies, several issues can arise. Firstly, overcrowding can occur. Over time, callalilies multiply and form dense clumps. Callalilies can thrive as houseplants as long as they have direct sunlight, regular repotting and dividing, and moist and fertile soil. Callalilies are perennials that can be separated and replanted to rejuvenate the plant and restore healthy blooming. The best time to dividecallalilies is in spring or fall, depending on... How to DivideCallaLily Plants. Here’s a simple step-by-step guide to safely dividing your callalilies: Gather Supplies. Sharp knife or garden shears. Callalilies do need to be divided every few years in order to keep them healthy. When you dividecallalilies, you’ll create smaller plants instead of one large plant.