To understand my watering needs, you must first understand what I am. I am a Lithops, a succulent native to the extremely arid, rocky deserts of southern Africa. My entire evolutionary purpose has been to survive in an environment where rainfall is infrequent, unpredictable, and often fleeting. My body is not a traditional plant with leaves and a stem; it is composed of two fused, succulent leaves that form a single, water-filled body. This pair of leaves is my reservoir, designed to store every precious drop of water I can get to endure months, or even an entire year, of drought. My flat top, or "window," allows sunlight to penetrate deep into my interior for photosynthesis while minimizing surface area exposed to the desiccating sun. Overwatering is not just a minor mistake for me; it is a catastrophic event that leads to rot and a swift, mushy death.
You cannot water me on a fixed schedule like a common houseplant. My needs change dramatically throughout the year, dictated by my innate growth cycle. My life revolves around four distinct phases, and your care must sync with them. During my active growth periods in late spring and autumn, I am building new leaves and flowering, and I will use the water stored in my old leaves. In the peak of summer, I enter a dormant state to protect myself from extreme heat, and in winter, I am dormant due to cooler temperatures and lower light. During these dormancies, my roots cannot take up water, and any moisture in the soil will be fatal.
The vast climate differences across the US mean you must observe local conditions, but my cycle provides the framework.
Spring (March-May): Water very sparingly, if at all. This is typically when I am absorbing my old leaves to fuel the growth of a new body from within. Wait until the old leaves have completely shriveled into a dry husk. Then, you may offer a very light watering to encourage root growth, but only if temperatures are consistently above 60°F.
Summer (June-August): Withhold all water. I am dormant. High heat and humidity in many US regions create a dangerous situation where my pot will not dry quickly, and I will easily rot. Protect me from excessive rain if I am outdoors.
Autumn (September-November): This is my primary growing and flowering season. You may begin watering again after the summer dormancy, but only when the soil is completely dry for several days. A good method is to wait until my tops begin to appear slightly wrinkled or puckered. Provide a thorough soak, then allow the soil to dry out completely again before even considering another watering.
Winter (December-February): Absolutely no water. I am completely dormant. Cool temperatures and wet soil are a lethal combination. My soil must stay bone-dry until spring arrives.
Your local environment within the US greatly influences these guidelines. A Lithops in dry, hot Arizona will have different evaporation rates than one in humid Florida. The potting mix is paramount; I must be planted in a very deep pot (to accommodate my long taproot) filled with a extremely gritty, fast-draining mix (80-90% mineral grit like pumice or perlite, 10-20% cactus soil). A clay pot is preferable to plastic as it breathes and helps soil dry faster. Always ensure I am in a location with several hours of direct sunlight daily and excellent air circulation to help moisture evaporate quickly after any watering.
