From our rooted perspective, the cycle of growth and rest is not a choice but a fundamental rhythm of existence, dictated by the sun, the rain, and the very tilt of the Earth. For us in the Crassula genus, dormancy is a vital survival strategy, a time to conserve our essence and prepare for the next season of abundance. Our dormancy periods are primarily dictated by our native habitats in South Africa and are generally categorized into two types.
Many of our most common relatives, like the Jade Plant (Crassula ovata), enter a state of dormancy during the hottest, driest part of the year, typically from late summer into early autumn. While the sun is most intense, our growth slows nearly to a halt. This is a protective measure. Our stomata, the tiny pores on our leaves, remain closed during the heat of the day to prevent precious water loss through transpiration. Without this gas exchange, photosynthesis is drastically reduced, and active growth ceases. Our energy is not spent on producing new leaves but on maintaining the health of our existing structures—our thick, succulent leaves and sturdy stems—which store the water and nutrients we need to survive the harsh conditions.
Another significant group within our genus, including varieties like the 'Calico Kitten' (Crassula marginalis rubra variegata), experience their dormancy during the cooler winter months. As daylight hours shorten and temperatures drop, our metabolic processes slow down. Cooler soil temperatures hinder our root system's ability to uptake water and nutrients efficiently. To avoid root rot in cold, damp soil and to prevent tender new growth that would be vulnerable to frost, we simply pause. We enter a state of rest, waiting for the stronger light and warmer soils of spring to signal that it is safe to resume active growth and photosynthesis.
Our physical form is perfectly adapted for these dormant periods. Our leaves are not merely for show; they are vast water reservoirs, allowing us to go for extended periods without moisture from the soil. Our CAM (Crassulacean Acid Metabolism) photosynthesis is the key. We open our stomata at night to take in carbon dioxide when evaporation rates are lowest, storing it as an acid. During the day, we use this stored carbon dioxide for photosynthesis while keeping our stomata sealed shut. This incredibly efficient system allows us to thrive with minimal water loss, making dormancy a successful strategy rather than a struggle.
You can observe clear signs when we enter dormancy. The most obvious is a complete halt in new growth. You will not see new leaves emerging or stems lengthening. Our water requirements diminish almost entirely; our soil will take much longer to dry out as we are not actively drawing moisture from it. During this time, the care we require changes significantly. Water must be withheld almost completely to prevent rot in our inactive root systems. Fertilizer should be entirely avoided, as we have no capacity to use the nutrients, and a buildup of salts in the soil can damage our roots. The ideal is to provide a cooler location with bright, indirect light for winter-dormant types and protection from the most intense afternoon sun for summer-dormant types.
