As a Crassula, I am a succulent, which means my tissues are designed to store water. This is a fantastic adaptation for hot, dry climates, but it becomes my greatest vulnerability in the cold. The water stored in my thick, fleshy leaves and stems is prone to freezing. When ice crystals form inside my cells, they expand and rupture the cell walls, causing irreversible damage. This manifests as soft, mushy, and discolored (often black or brown) leaves—a condition you know as frost damage. My roots are also highly susceptible to rot if they sit in cold, wet soil. Therefore, my entire winter survival strategy revolves around staying dry and above freezing.
You must understand that I am not actively growing during the cold, short-day months. I enter a state of dormancy. My metabolic processes slow down significantly. Because I am not growing, my water requirements drop dramatically. The single most important rule for my winter care is: less water. Overwatering while I am dormant and cold is a sure way to kill me via root rot. The goal is to keep my soil barely moist, almost completely dry, between waterings. I can easily survive a month or more without a drink if the temperatures are cool. Please, err on the side of underwatering.
I cannot survive a true frost outdoors. As temperatures consistently drop below 50°F (10°C), I need to be brought inside. My preferred winter spot is a bright, cool room. An unheated sunroom, a bright garage with a window, or a south-facing windowsill inside your home is perfect. I need as much direct sunlight as possible to maintain my compact shape and prevent etiolation (becoming leggy and stretched). The ideal temperature range for my dormancy is between 45-55°F (7-13°C). While I can tolerate the warmer and drier air of your heated living room, the combination of low winter light and warm temperatures can cause weak, stretched growth.
My watering needs are minimal. Please water me only when the soil is completely dry to the touch, and do so sparingly. Water me just enough to moisten the roots, but never to the point where water flows freely from the drainage hole. Do not fertilize me at all during winter. I cannot use the nutrients, and the salts in the fertilizer will simply build up in the soil and potentially burn my sensitive, dormant roots. Hold off on any repotting until the active growing season in spring. Finally, please keep an eye out for pests like mealybugs and spider mites, who are more prone to infest stressed plants indoors. A quick spot treatment with isopropyl alcohol on a cotton swab is an effective remedy.
If I am too large to move or am planted in the ground in a marginally cold climate, I will need significant protection. A deep layer of dry mulch like straw or bark can help insulate my root zone. However, my above-ground parts are still exposed. For short, sharp frosts, you can cover me with a frost cloth or blanket overnight, but this must be removed during the day. For anything more severe, a temporary cold frame or greenhouse structure is my only hope for survival outdoors. Remember, my tolerance is limited, and prolonged freezing temperatures will be fatal.
