Ixia, commonly known as African Corn Lilies or Wand Flowers, are popular garden plants valued for their bright, star-shaped blooms that appear in late spring and early summer. Originating in South Africa, these perennials are well-suited to warmer climates and reliably add color to mixed borders or container plantings. Ixia multiply readily, allowing a single planting to quickly develop into a dense, flowering clump over several seasons.
Understanding Ixia Corms and Offsets
Ixia multiplication centers on its underground storage structure, which is technically a corm, not a true bulb. A corm is a swollen stem base composed of solid, dense stem tissue, unlike a true bulb made of fleshy layers of modified leaves. During the annual growing cycle, the parent corm is consumed, providing the energy required for the plant’s growth and floral display.
As the parent corm is depleted, a new, larger replacement corm forms directly on top of it to store energy for the following year. Simultaneously, several smaller miniature corms, known as cormels or offsets, develop around the base of this new structure. These offsets are clones of the parent plant and are the primary way Ixia naturally increases its numbers. Each cormel will mature into a flowering-size corm capable of producing its own blooms and offsets.
When and How to Divide Crowded Clumps
The natural proliferation of offsets means Ixia clumps will eventually become overcrowded, necessitating periodic division to maintain plant vigor. Overcrowding causes competition for nutrients and moisture, resulting in fewer flowers and smaller, weaker plants over time. Dividing the clumps every three to five years is sufficient to prevent this decline and refresh the planting area.
The best time to divide Ixia is after the foliage has naturally yellowed and died back, signaling the plant has entered its summer dormancy. This timing, usually in late summer or early fall, allows the corms to be handled while they are resting before the next season’s root growth begins. Carefully lift the entire clump from the soil using a garden fork, taking care to avoid damaging the corms.
Once lifted, gently separate the new corms and cormels from the remains of the old, shriveled parent corm. The corms should be brushed clean of excess soil and allowed to cure in a dry, shaded, and well-ventilated location for about a week. This curing period helps the outer skin, or tunic, harden, which protects the corms from rot and disease during storage.
The larger, flowering-size corms can be immediately replanted at a spacing of about 3 inches apart. Alternatively, they can be stored in a cool, dark, and dry environment, such as a paper bag filled with peat moss, until the optimal autumn planting window.
Growing New Ixia from Seed
While corm division is the fastest and most reliable method for generating new plants true to the parent variety, Ixia can also be propagated from seed. Growing from seed is a slower process, often used for propagating species rather than hybrid cultivars, as resulting plants may not resemble the parent. Seeds can be collected from dried seed pods after the flowering season concludes and the pods turn brown.
Ixia seeds should be sown in the autumn in a well-draining soil mix and kept barely moist through the cooler months. The seeds will germinate within four to six weeks, producing grass-like seedlings that grow throughout the winter and spring. Seed-grown Ixia plants require two to three years of growth before the corms reach a mature, blooming size.