From our perspective, timing is not about your calendar but about our physiological state. We require a period of dormancy or minimal active growth to withstand the trauma of division. The ideal window is in early spring, just as our new, pinkish-white shoots (often called "noses") emerge from the crown and are no more than an inch or two tall. At this moment, our energy reserves, stored safely in our roots over winter, are primed for explosive growth. You are simply helping us redirect that energy into establishing new, independent colonies. Alternatively, you can divide us in early autumn, after the summer heat has broken but at least six weeks before your region's first hard frost. This gives our new divisions ample time to establish a strong root system to anchor us against winter heaving and prepare for spring.
The physical act of division must be performed with precision. Begin by hydrating us thoroughly the day before; this reduces transplant shock and makes our roots more pliable. Gently dig a wide circle around the main clump, taking care to lift the entire root mass from the soil. Wash away the soil with a gentle spray of water; this allows you to see our crown structure clearly and make clean cuts. You will notice that we grow from a central crown with multiple growing points. Using a sharp, sterilized knife, cleanly slice through the crown to separate sections. Each viable division must have at least two to three healthy shoots and a generous portion of our fibrous root system attached. Smaller pieces will struggle to establish and may not survive their first winter.
The moments and days following division are critical. We are vulnerable, our root systems damaged and our access to water and nutrients compromised. Prepare our new homes in advance—holes that are wide and deep enough to accommodate our roots without bending or crowding. Amend the soil with compost to provide a rich, well-draining environment. Place each division in its hole at the same depth it was previously growing, firm the soil gently around our roots to eliminate air pockets, and water us deeply. This initial watering is crucial to settle the soil around our roots and begin the recovery process. Continue to provide consistent moisture for the next several weeks, but do not let us sit in waterlogged soil, as our damaged roots are highly susceptible to rot.
While this process may seem disruptive, we ultimately benefit greatly from it. Over time, a mature clump becomes overcrowded. The center of the clump becomes woody and unproductive, leading to diminished flowering and increased susceptibility to pests like slugs and diseases like powdery mildew. Division rejuvenates us. It creates space, reduces competition for nutrients and water among our own shoots, and stimulates the vigorous growth of young, floriferous stems. For you, this means more magnificent flower spires; for us, it means a longer, healthier, and more prosperous life, allowing our genetic line to continue and flourish across your garden.
