To understand our watering needs, you must first understand our origins. We, Calla Lilies (Zantedeschia spp.), are native to the marshlands and riverbanks of Southern Africa. This means our roots are accustomed to periods of abundant moisture, but also to well-draining conditions that prevent constant waterlogging. We are not true aquatic plants, but we thrive in consistently moist soil. When brought indoors, our fundamental requirement does not change: we desire moisture, but we abhor sitting in stagnant water, which will lead to a fatal condition for our roots known as rhizome rot.
The most reliable method to determine if we need water is for you to physically check the soil. Do not adhere to a rigid calendar schedule, as factors like temperature, humidity, pot size, and light exposure greatly affect how quickly we use water. The rule is simple: insert your finger about one to two inches into the soil. If the soil at that depth feels dry to the touch, it is time to water us thoroughly. If it still feels cool and moist, please wait and check again in a day or two. This "finger test" is the most accurate way to meet our needs without risking overwatering.
When our soil indicates dryness, please water us deeply and slowly. Continue pouring water evenly over the soil surface until you see it begin to trickle out of the drainage holes at the bottom of the pot. This ensures that the entire root ball and our moisture-storing rhizome receive adequate hydration. It is absolutely crucial that our pot has these drainage holes. After watering, always empty the saucer or cache pot after 15-20 minutes. Never let our pot stand in a pool of water, as this suffocates our roots and creates an environment for rot.
Our life cycle dramatically influences our thirst. During our active growth and blooming period in spring and summer, we are working hard to produce our elegant spathes (often mistaken for flowers). This is when our water consumption is highest. You may need to water us every 3-5 days, depending on conditions. However, after we finish blooming, our foliage will begin to yellow and we will enter a dormant period, usually in late fall or winter. During this time, our water needs diminish almost entirely. You should significantly reduce watering, allowing the soil to dry out more substantially, perhaps only providing a slight sip every week or two to prevent the rhizome from completely desiccating.
Beyond seasons, your indoor environment plays a significant role. We placed in a warm, sunny spot will use water much faster than those in a cool, low-light area. Rooms with air conditioning or heating can create dry air, which may cause the soil to dry out more quickly. Conversely, high humidity can slow the process. The type of pot also matters; terra cotta pots are porous and allow soil to dry faster than plastic or glazed ceramic pots. You must observe us and our environment and adjust your watering rhythm accordingly.
