Lily of the valley are small plants that spread through horizontal rhizomes. The small bell-shaped flowers produce a strong perfumed fragrance. According to the University of Illinois, the lily of the valley is best replanted in the fall prior to any late freezes. As with most lilies, the plants will do well if divided and replanted approximately every three years to prevent overcrowding. Little fertilization is required for this plant. In fact, excessive nitrogen will cause the lily of the valley not to bloom due to unnecessary leaf growth.
Prepare a new lily of the valley flowerbed. Dig the area to a depth between 6 inches and 8 inches deep. All lilies enjoy a well drained soil, with sun light exposure between six hours to 10 hours a day.
Amend the soil with up to three bushels of peat moss per 100 square feet of flowerbed, if the soil is heavy in clay. Work the organic material into the soil to a depth of 8 inches.
Water the existing lily of the valley flowers two days to three days prior to replanting.
Dig the lily of the valley plants from the ground using the hand spade. The moist soil will aid in removing the rhizome clumps from the soil.
Shake the loose soil from the plant roots, or hose the roots to expose the small rhizomes. Separate the plants into small clusters, or into individual plants called pips.
Place the individual rhizomes or clusters of lily of the valley plants into the new flowerbed. Leave approximately 3 to 5 inches between each cluster if you plan to divide again in three years. Leave a greater spacing if you wish to divide at a later date (more than three years).
Set the plants at a depth where the rhizomes reside just under the soil line. Press the loose soil firmly around the roots of the plant.
Water the new plants location thoroughly to remove air from around the roots system and improve the soil to root contact.
Layer mulch around the new plants, up to 2 inches thick, to reduce any winter frost heaving.