From our perspective, deep in the soil, the primary reason for division is simple: space. We grow from underground storage structures called rhizomes. As we mature each season, our rhizomes expand outward, sending up new sets of leaves, called "eyes" or "fans," from growing points known as crowns. Over time, a single plant can become a large, dense clump. While this might look impressive above ground, beneath the surface we become crowded. This congestion leads to intense competition among our own roots for water, nutrients, and space. Our central, older rhizomes may even begin to die back, leaving a hollow ring of growth and causing our vibrant foliage to diminish in size. Division is not a punishment; it is a necessary rejuvenation that mimics how we would naturally spread in a forest setting.
We will tell you when the time is right. The most obvious signal is our appearance in early spring. As we emerge from dormancy, if you see a dense ring of crowded shoots pushing up from the soil with a dead or less vigorous center, we are asking for help. This is our prime time for division. The cool, moist conditions of early spring, just as our new eyes are a few inches tall, provide the least amount of stress. The energy stored in our rhizomes is directed towards root production rather than supporting large, mature leaves, which can wilt easily if disturbed. Alternatively, you can divide us in early autumn, once the stifling heat of summer has passed but we still have enough warm weeks left to establish new roots before the winter freeze.
The process requires a gentle hand. First, use a sharp spade or garden fork to dig a wide circle around our entire drip line, carefully lifting the entire clump from the earth. Wash or gently shake off the soil from our root mass so you can clearly see the structure of our rhizomes and the natural divisions between the fans. The goal is to minimize damage. You can often tease smaller clumps apart with your hands, but for mature, tough clumps, you may need to use two garden forks inserted back-to-back into the center and levered apart, or a sharp, sterilized knife to cut through the rhizomes. Ensure each new division has at least three to five eyes and a healthy portion of our roots attached. This gives the new plant the best chance to thrive independently.
After division, we require careful replanting to ensure a swift recovery and a lush future. Prepare the new planting holes with ample organic matter to welcome our roots. The hole should be wide and deep enough to accommodate our root system without bending or crowding. Place the division in the hole so that the crown, where the roots meet the shoots, is level with the surrounding soil surface. Backfill gently, firm the soil around us to eliminate air pockets, and water deeply and thoroughly. This initial watering is crucial to settle the soil around our roots and help us recover from the shock. A layer of mulch will help conserve moisture as we begin our new chapter of growth, quickly developing into a strong, vibrant plant that will contribute to the lushness of your garden for years to come.
