Lilies are perennial garden plants known for their striking blooms and architectural presence. Over several growing seasons, these bulbous plants naturally multiply, forming dense clumps that can eventually become overcrowded. To ensure the continued health and vigorous flowering of the plants, relocation or division becomes a necessary task. Understanding the optimal timing and following the correct procedure for this maintenance activity is important for success.
Optimal Timing for Moving Lilies
The most favorable period for moving true lilies (Lilium genus) is during their natural dormancy in late fall. This timing, typically late September through October, allows the bulbs to be lifted after the plant has finished seasonal growth and stored maximum energy. Waiting until the foliage has yellowed and completely died down indicates this period of rest, ensuring minimal shock upon relocation.
While late fall is the preferred window, lilies can also be moved in early spring before new shoots emerge, though this carries a higher risk. Transplanting in spring means the bulbs have less time to establish new roots before the demands of the growing season begin.
Moving them after significant new growth has started risks breaking off the fragile sprouts, which often results in the loss of that year’s bloom. The principle of transplanting during dormancy holds true for all common types, including Asiatic, Oriental, and Trumpet lilies.
Identifying the Need to Move Lilies
An established lily clump typically signals its need for division or relocation after three to five years, though the exact timing depends on local conditions and the specific variety. The most common sign of overcrowding is a reduction in the size or quantity of flowers produced on a stem. Competing bulbs vie for finite resources, causing robust stalks to produce spindly growth, narrower flower buds, and shorter stems.
Relocation may also be necessary due to environmental factors, such as a change in the garden’s light conditions caused by a maturing tree or shrub. Lilies require at least six hours of direct sunlight daily to flower reliably, and diminished light results in poor performance. Moving the bulbs to a new, suitable location is necessary to restore the plant’s vigor.
Executing the Transplant Procedure
Transplanting should be executed efficiently to minimize the time the delicate, scaley bulbs are exposed to air and potential drying. Begin by preparing the new planting site, ensuring the soil is well-drained and amended with compost or organic matter. The new planting hole should be ready before the lilies are lifted, preventing any delay in replanting.
To lift the bulbs, cut the existing foliage back to about six inches above the ground, then dig a wide circle at least 12 inches deep around the plant to avoid damaging the root system. Gently pry the entire clump from the soil and brush off excess dirt to expose the clustered bulbs and bulblets. Separate the individual bulbs by hand, discarding any that show signs of disease or rot, and removing any damaged or broken roots.
Place the larger, mature bulbs at a depth of five to six inches; smaller bulblets should be planted closer to the surface, about two to three inches deep. Ensure the pointed end of the bulb is oriented upward, and space the bulbs eight to twelve inches apart to allow for future growth. Replant the bulbs immediately and water them well to settle the soil around the basal roots.
Ensuring Success After Replanting
Following transplanting, the priority is to settle the bulbs into their new location and facilitate root establishment. Give the newly planted area a deep, thorough watering to eliminate air pockets in the soil and provide initial moisture. After this initial soak, maintain consistent, moderate watering during the first few weeks, ensuring the area does not become saturated or waterlogged.
Applying a thick layer of mulch, such as shredded bark or straw, over the replanted area helps retain soil moisture and insulates the bulbs from temperature extremes, which is particularly beneficial for fall transplants. It is common for transplanted lilies to skip blooming in the first year as they dedicate their energy to developing a robust root system. This focus on underground recovery sets the stage for a spectacular display in subsequent seasons.