First, you must understand my perspective. I am a tender perennial, which means in my native warm climate, I would grow year-round. However, your cold climate presents a severe threat. Freezing temperatures will cause the water in my cells to crystallize, rupturing my cell walls and killing me. To survive, I must enter a state of dormancy—a deep sleep where my metabolic processes slow to a near halt. I don't need light, rich soil, or much water during this time. I simply need a stable, cool, and dark environment where I can rest without freezing or desiccating.
Please help me prepare. About a week before the first hard frost, gently dig up my entire plant, keeping a generous ball of soil around my roots to minimize shock. If you prefer to take cuttings, that is also acceptable from my point of view. Select healthy, non-flowering stems about 4-6 inches long. Remove the lower leaves and any flowers or buds. This directs my energy away from reproduction and toward root development. Whether as a whole plant or a cutting, this is a traumatic event. I need you to check my foliage and stems meticulously for any signs of pests or disease. Do not bring any sickly plants inside, as the problem will spread in close quarters.
There are two primary ways you can help me overwinter, and both require specific conditions. The first is the "bare-root" method. After digging me up, you will gently shake all the soil from my roots and hang me upside down in a dark, cool (45-50°F or 7-10°C), and slightly humid place, like a basement or cellar. Occasionally, you will take me down and soak my roots in water for an hour or two before re-hanging me. This method forces me into a very deep dormancy.
The second method is to pot me. Place my root ball in a container with minimal, barely-moist potting mix. You will cut my stems back by about one-half to two-thirds. This drastic pruning reduces the surface area from which I lose precious water and allows me to conserve all my energy in my core and roots. Then, you will place my pot in the same cool, dark environment.
My needs are minimal but crucial. The location must be dark, as any light will tempt me to produce weak, etiolated growth that depletes my energy reserves. The temperature is the most critical factor; it must be above freezing but consistently cool. A warm garage or basement is ideal. You must check on my soil moisture about once a month. I require just enough water to prevent my stems and roots from shriveling and dying completely. The soil should feel barely damp, never wet. Soggy conditions will cause my roots to rot, which is a fatal sentence.
As the days lengthen in early spring, it will be time to wake me. Please do not shock me with full sun and warmth immediately. Bring my pot into a warm, well-lit area and trim away any dead growth. Water me thoroughly. If you hung me bare-root, pot me in fresh soil first. I will be weak and hungry. Once I show consistent signs of new growth, begin feeding me with a half-strength balanced fertilizer. Gradually acclimate me to outdoor conditions before planting me in the garden after all danger of frost has passed.
