The daylily (Hemerocallis) is a popular, hardy perennial prized for its trumpet-shaped flowers. These resilient plants form dense, clumping root systems that thrive for years with minimal attention. Propagating daylilies is a straightforward way to increase your stock of a favorite variety. Periodic propagation is also helpful for maintaining the health and vigor of established, overcrowded plants.
Optimal Timing and Necessary Preparation
The best times for propagating daylilies by division are in the early spring, just as new growth emerges, or in the late summer and early fall after blooming. If dividing in the fall, time the activity to occur at least four to six weeks before the expected first hard frost. This allows the newly separated roots time to establish themselves. Gather necessary tools, including a sturdy garden spade or fork, a sharp knife or hand pruners, and water to clean the root clumps.
Water the daylily clump thoroughly a day or two before digging it up; this moistens the soil and makes lifting the root ball easier. Having a tarp or wheelbarrow on hand is beneficial for temporarily placing the large clump after removal. This preparation minimizes the time the roots are exposed to the air, ensuring a smooth transition.
Step-by-Step Guide to Division
Start the division process by inserting a garden fork or spade 6 to 12 inches away from the center of the clump to avoid damaging the crown. Work around the plant, leveraging the tool to loosen the soil and lift the root ball out of the ground. Once the clump is free, gently shake or wash off the excess soil with a hose to expose the fleshy roots and the individual fans of foliage.
Examine the clump to identify the natural divisions, which appear as individual fans of leaves connected to the crown and a cluster of roots. The goal is to separate the mass into smaller sections, each containing a minimum of two to three healthy fans and an attached root system. For tightly bound clumps, use a sharp knife or spade to slice through the rhizomatous crown tissue to achieve clean divisions.
After separating the fans, use sharp shears to trim the leaves back to a height of about 6 to 12 inches. This “haircut” reduces water loss through transpiration and focuses the plant’s energy on root establishment. Prune any dead, damaged, or overly long roots, cutting them back to about 4 to 6 inches to encourage the growth of new feeder roots.
Alternative Methods: Seeds and Proliferations
While division produces a genetic clone of the parent plant, using seeds is the primary method for hybridizers developing new varieties. Seeds are collected from dried seed pods that form on the spent flower scapes. They require cold stratification to break dormancy, which involves exposing the seeds to cold, moist conditions, typically by refrigerating them for three to six weeks before sowing.
Proliferations are small plantlets that occasionally develop along the flower stem, or scape. These clones can be removed once they have developed small aerial roots or the scape begins to brown and dry. Clip the proliferation off with a small section of the scape attached, and then root it in a moist potting medium.
Ensuring Successful Establishment
When replanting divisions, dig a hole wide enough to spread out the roots, creating a small mound of soil in the center. Position the plant so the crown (where the roots and leaves meet) is approximately one-half to one inch below the soil surface. Planting too deeply is a common error that can hinder the division’s ability to establish quickly.
Gently backfill the hole with soil, firming it lightly around the roots, and immediately water the new transplants thoroughly to settle the soil and remove air pockets. Maintaining consistent moisture is important during the first few weeks following propagation to support new root growth. Applying a two-inch layer of organic mulch around the plant helps conserve soil moisture and moderate temperature fluctuations.
If fertilizing the newly planted divisions, use a balanced, low-nitrogen formula (such as a 5-10-10 or 10-10-10 blend) to encourage root and bloom development rather than excessive foliage growth. Continued watering, particularly in dry conditions, will ensure the new daylilies establish a strong root system and begin vigorous growth.