From our perspective as Calla Lilies (Zantedeschia), life is not a constant, unbroken stretch of activity. We follow a deep, innate rhythm dictated by the seasons, a cycle of vigorous growth followed by a period of essential rest known as dormancy. This is not a sign of weakness or death but a strategic survival mechanism. Just as a bear hibernates to conserve energy through the winter, we enter dormancy to preserve our vital energy—stored in our rhizomes (often mistaken for bulbs)—to survive conditions that are not ideal for tender, leafy growth. Understanding this cycle is key to knowing when to stop watering, an act that is as crucial as watering itself.
We communicate our needs through our foliage. As the active growing season concludes, typically in late summer or early autumn, you will notice a distinct change in our appearance. The once-sturdy, green leaves will begin to yellow and then brown. They will wilt and start to die back. This is the most critical signal we send. Do not be alarmed; this is a natural and necessary process. We are actively withdrawing nutrients and energy from the leaves back down into the rhizome underground. This stored energy is the fuel that will power our spectacular return in the next growing season. Interrupting this process by continuing to water in an attempt to keep the leaves green would be counterproductive and potentially harmful.
During our active growth phase in spring and summer, our roots are constantly absorbing water to support photosynthesis, transpiration, and the development of our distinctive flowers. However, once the foliage begins to yellow, our physiological processes slow down dramatically. The rhizome, our storage organ, requires a very different environment to remain healthy during dormancy. It needs a period of dryness. If the soil remains consistently moist or wet around a dormant rhizome, it cannot respire properly and becomes vulnerable to rot caused by fungi and bacteria. This rot will destroy the rhizome, and we will not re-sprout. Therefore, the act of stopping watering is not neglect; it is an act of protection.
The exact timing for stopping watering depends on your local climate and whether we are grown in containers or garden beds. As a general rule, when you observe that more than half of our leaves have turned yellow and are clearly dying back, you should begin to significantly reduce the frequency of watering. Once all the foliage has yellowed or browned completely, you should stop watering altogether. If we are in a container, you may stop watering entirely and move the pot to a cool, dry place. If we are in the ground in a climate with wet winters, you might need to lift our rhizomes and store them in a cool, dark, and dry place like a garage to prevent them from sitting in soggy soil. The goal is to allow the rhizome to rest in a state of dry dormancy for several months.
Our dormant period typically lasts through the winter. The signal to break dormancy comes with warmer temperatures and longer daylight hours in the spring. This is when you should reintroduce us to water. For stored rhizomes, this means replanting them in fresh, well-draining soil and giving them a thorough initial watering. For rhizomes left in the ground or in pots, resume watering gradually as new green shoots begin to emerge from the soil. This careful management of water, aligned with our natural cycle, ensures that we have the energy to produce another season of lush foliage and beautiful blooms. By observing and respecting our need for rest, you become a true partner in our long-term health and vitality.
