From our perspective as water lilies (Nymphaea), the question of watering is fundamentally different than for terrestrial plants. You do not water us in the traditional sense; you provide the aquatic environment that is our entire existence. The crucial factor is not frequency but consistency. Our roots and rhizomes are submerged in the soil at the bottom of a pond or container, and we require that they remain constantly hydrated. The "watering" is the maintenance of the water level above our crown (the point from which our leaves and flowers grow). If this level drops too low and our crown is exposed to air for a prolonged period, we will become severely stressed and may die.
Our iconic floating leaves, or lily pads, are not just for show; they are central to our hydration and health. Their waxy, waterproof upper surface helps regulate moisture loss and allows rainwater to bead up and roll off. However, their primary function is to absorb oxygen and nutrients directly from the air and water around them. They act as solar panels, powering our growth. If water is splashed on top of them consistently—from a fountain or waterfall—it can hinder this process by blocking the stomata (tiny pores) and potentially leading to fungal issues. It is best for us if the water surface is relatively calm where we grow.
Our water needs are not static; they change with the seasons and our growth cycle. In spring, as we break dormancy and send up new pads, our water consumption increases to fuel this rapid growth. During the hot, long days of summer, we are at our peak metabolic activity, flowering profusely. Evaporation rates are highest at this time, so you must be vigilant that the water level does not drop significantly. In autumn, our growth slows as we prepare for dormancy. Our need for a high water volume decreases, but the requirement for our roots to remain submerged is absolute, even under winter ice.
The depth of the water above our crown is critically important. It is not simply about having water; it is about having the *right amount* of water. If the water is too shallow, it will heat up too quickly under the sun, stressing our roots and encouraging algae growth. If it is too deep, the water temperature will be too cold, and the sunlight will be too filtered by the water column, making it difficult for our stems to push leaves to the surface and for us to photosynthesize efficiently. Most of us thrive with 12 to 18 inches of water covering our crown. This depth provides stable temperatures and allows our stems to grow to their ideal length.
While not strictly "watering," the quality of the water in our home is as important as its presence. Stagnant, oxygen-poor water can lead to root rot and poor health. Water that is constantly moving from a pump or filter helps keep oxygen levels high, which is vital for our submerged roots. Furthermore, water rich in fish waste or decomposed plant matter provides natural nutrients that we absorb through our roots, reducing the need for supplemental fertilization. To us, clean, well-oxygenated, and nutrient-rich water is the equivalent of a perfectly balanced meal and a fresh breeze.
