My garden includes several gladioli. I do not recall planting even one of these plants, but there they are, almost always in the wrong places. They have popped up, for example, in the middle of the rose bed, and on the edge of the entry path to my front door.

One definition of weeds is “plants that grow where they are not wanted,” but these plants have attractive blossoms. In fact, the sword lily—as it is sometimes called—is among the most desirable plants for cut flowers. The blossoms are available in many different colors.

Now that their blossoms have faded and the stalks are drying out, it’s the right time to corral their spread and get them growing in better places. This calls for some research.

The genus Gladiolus is a member of the iris family (Iridaceae), including about 300 species, the large majority of which are natives of South Africa. The species range in height from 1.5 feet (G. tristis) to 3 feet (G. callianthus, the Abyssinian Sword Lily) to 6 feet (the common grandiflora hybrids).

Gladiolus byzanthus
By Meneerke bloem

The 5.5 feet plants that have appeared are probably garden hybrids and are best placed in the middle or back of the bed.

Once the plant’s blossoms have turned brown, the stems should be cut below the lowest flower to discourage the plant from setting unwanted seeds. In the Monterey Bay area’s moderate climate the corms can be left in place, or dug for planting in a different location. My garden is organized geographically, so I will replant the corms in the South African bed.

Once dug, the corms can be grouped in three categories: old, large corms are viable but lack vigor; younger corms at least .75 inches in diameter will produce blossoms in the spring; and cormlets about the size of peas can be planted to produce blossoms after a year of development.

Corms may be stored in a cool, dry, dark and well-ventilated place until replanting in the following year from January to March. After planting they will bloom reliably in 80–to–100 days, depending on the variety. This invites succession planting about 1 or 2 weeks apart to yield a series of blooms for cutting or enjoying in the garden.

The corms should be planted where they will get rich soil, full sun, and good drainage. They should be planted about 4 inches deep and about 6 inches apart. Apply an organic, water-soluble fertilizer when the plants are 10 inches tall, and again when the flower spikes begin to show color.

As the plants grow, they might require staking, either with individual stakes or a grid made of stakes and string (but almost none one of the several volunteers in my garden has flopped).

As sometimes happens, plants that introduce themselves unexpectedly in the garden can be appreciated and welcome. So far, I am glad to discover gladioli and looking ahead to a fine display in the spring and summer of next year. I might even become interested in buying corms of different species and different colors.

For information about gladiolus varieties and cultivation of these plants, visit the website of the North American Gladiolus Council.