From our perspective, we are not true tropical plants, but rather subtropical natives of South Africa. We can tolerate brief dips in temperature, but sustained cold is our greatest enemy. Our cells contain water, and when temperatures drop below freezing (32°F or 0°C), that water freezes, expands, and ruptures our cell walls. This causes the black, mushy damage you see on our beautiful, broad leaves. While we can survive a very light frost with some protection, our goal is to avoid freezing temperatures entirely. In a "mild climate," this typically means ensuring temperatures do not remain below 50°F (10°C) for prolonged periods, especially at night.
Our placement in your garden is the single most important factor for our winter survival. We implore you to plant us in a location that mimics our native habitat. We crave a spot with full sun exposure to keep us warm and aid in photosynthesis during the shorter days. Crucially, we need exceptional shelter. Plant us on the south or west side of your house, snug against a warm wall that will radiate residual heat back onto us throughout the night. This wall also acts as a vital windbreak. Cold, harsh winds strip moisture from our leaves and drastically lower our tissue temperature, increasing the risk of frost damage. A spot under the eaves of the roof can also provide valuable protection from excess winter rain.
As the days shorten and temperatures cool, our growth slows significantly, and our need for water and nutrients diminishes almost entirely. Please, drastically reduce your watering frequency. Soggy, cold roots are a death sentence for us, leading to rapid root rot. Allow the top several inches of soil to dry out completely between waterings. Furthermore, you must cease all fertilization in the late fall and throughout the winter. Feeding us while we are dormant will force tender new growth that is exceptionally vulnerable to cold damage and will weaken our overall system as we try to rest.
Even in mild climates, unexpected cold snaps happen. For these events, we require you to provide us with a protective blanket. When a frost or freeze is forecast, cover us completely with a breathable fabric like frost cloth, burlap, or an old blanket. Do not use plastic sheeting, as it traps moisture against our leaves and can cause more damage when it touches the foliage. Drape the material over us just before sunset to trap the day's residual ground heat, and secure it at the base without crushing our stems. Remember to remove the covering once temperatures rise above freezing the next morning to allow for light and air circulation. A thick, dry layer of mulch (like wood chips or straw) piled 3-6 inches high around our base is also essential. This insulates our most vulnerable part—the root crown—from freezing temperatures.
