Liatris, commonly known as Blazing Star or Gayfeather, is a hardy perennial grown from a corm. Gardeners often transplant Liatris to manage overcrowding, which reduces flowering, or to move it to a better location. Successful transplanting requires minimizing stress, achieved by correct timing and careful handling of the root system.
Optimal Timing for the Move
The best time to transplant Liatris is when the plant is dormant, which significantly reduces the risk of transplant shock. There are two primary windows for this process: early spring and late fall.
Early spring is often the preferred time, just as new growth begins to emerge from the soil. At this stage, the plant has not yet committed energy to producing foliage or flower stalks, meaning the root system is less stressed. Look for tiny red or green shoots, typically less than three inches tall, as your cue to begin digging.
The second optimal period is late fall, after the foliage has died back and the plant has entered dormancy. Transplanting allows the corms to settle into their new location over the winter months, ready to begin root growth as soon as the soil warms up.
Avoid transplanting Liatris during the active growing season, especially when flowering or in the heat of summer. Moving an actively growing perennial forces it to divert energy to root repair, which can lead to severe transplant shock and even plant death.
Preparing the Plant and Dividing Clumps
Before digging, prepare the Liatris clump by cutting back the spent flower stalks and foliage near ground level. If the soil is dry, water thoroughly the day before the move. This helps keep the root mass intact and reduces stress on the corms.
To lift the plant, use a sharp spade or shovel and begin digging a circle a few inches outside the perimeter of the existing growth. Dig at a slight angle, aiming to get underneath the corm mass. Gently lever the entire clump out of the ground, preserving as much of the root system as possible.
Liatris corms naturally multiply over time, forming large, dense clumps that should be divided every few years. Once the clump is out of the ground, remove excess soil to better see the individual corms or the woody corm mass.
Use a clean, sharp tool like a garden knife or pruning saw to cut the corm mass into smaller sections. Ensure that each new division contains at least one healthy corm and some viable roots or a visible “eye” or bud for future growth.
Ensuring Transplant Success
The new planting site should meet the Liatris’s preference for full sun and well-draining soil. Since the plant is susceptible to root rot in overly wet conditions, drainage is a major factor. If the existing soil is heavy clay, amending the area with compost before planting will improve drainage.
Dig a hole large enough to accommodate the new division comfortably. Set the corm or clump into the hole so the top is at the same depth as it was previously. For individual corms, the planting depth is typically around five inches.
After placing the division, backfill the hole with soil, gently tamping it down to remove air pockets around the roots. The most important step immediately following transplanting is a deep initial watering. This deep soak settles the soil around the corms.
For the first few weeks, maintain consistent moisture as the plant establishes new roots. A layer of organic mulch, such as shredded bark or straw, applied around the base helps conserve soil moisture and regulate temperature. Consistent watering during this initial period is crucial for a successful transition.