Gladiolus

Colorful Combinations

In the garden or in a vase, gladiolus adds garden-fresh drama. An old-fashioned flower originally from South Africa, the lofty flower spikes of gladiolus emerge from disc-shaped corms that are planted in spring. When done right, fresh-cut flower spikes will last for more than a week in a vase. Search your favorite online bulb retailer for glads—you’ll find varieties with blossoms in nearly every color of the rainbow.

Garden Design Tips

Call on gladiolus when you need a dramatic focal point in the garden or bold vertical structure. The sword-shape foliage and upright flower stalks draw attention. Pair gladiolus with dahlias, peonies, and other sturdy perennials that can provide support for these tall, petal-packed flower spikes.

If you are growing gladiolus primarily for cut flowers, plant the corms in rows as you would vegetables. Row planting makes for easy soil preparation, planting, staking, and harvesting in mid-summer. Add a row of gladiolus to your vegetable garden, planting the corms at the same time you plant tomatoes. Continue planting gladiolus every couple of weeks for a continuous cut-flower harvest.

Gladiolus Care Must-Knows

Gladiolus thrive in full sun and well-drained soil. They will bloom in shade, but the flowers will be smaller and the flower stalks will be floppy. Quick-draining soil is also essential for this plant to thrive. If your soil is filled with clay, is too wet, or is boggy, you should plant gladiolus in raised beds instead. These flowers are tender bulbs, which means they are not winter hardy in garden Zones 7 and lower. Glads must be planted every spring in these areas, as they will overwinter in the garden only in Zones 8–10. You can begin planting gladiolus corms in spring when the soil has started to warm—usually in April or May.

Need help getting started? Be sure to plant the pointed side of the corms up, about four times as deep as their width. Space the glad corms 6 to 8 inches apart. If you are planting gladiolus in a garden bed, plant in drifts of at least 7 bulbs for a pleasing display. Spread a 2-inch-layer of mulch on the soil surface and water the newly planted corms well. Leaf stalks will emerge in a couple of weeks.

Harvest Glads For Weeks

Harvest bouquets of glads for six weeks or more in summer by staggering the planting of corms. Plant a group every two weeks in spring. Stop planting in mid-June to give the plants plenty of time to mature before a damaging freeze in fall. When planting long rows of corms to use as cut flowers, plan to stake each stem along one side of the row, tying the stems to the panel as they grow.

To ensure that your harvest will last, only cut the flower spikes after one or two blossoms are open. The remainder of buds will follow in the first bloom’s footsteps. Immediately plunge the stems in lukewarm water. As lower flowers fade, pull them off and cut about an inch of the stem off the bottom of each spike every few days.

Storing Glad Corms

In Zones 7 and below, glad corms can be dug out in the fall and stored for planting back in the garden in springtime. Once a harsh frost kills gladiolus foliage, dig up the corms. Shake off excess soil and place the corms in a warm, dry, airy place for about three weeks. Make sure to get rid of any shriveled, old, spent corms, placing the healthy bulbs in a paper sack to store in a cool and dry place until spring. Many gardeners choose not to dig and store glads, but instead purchase new corms each year. The choice is yours!

More Varieties of Gladiolus

Abyssinian gladiola

Gladiolus callianthus var. murielae is unique because it sports extremely fragrant, butterfly-shaped flowers on arching stems in late summer. The white petals have deep purple centers. It grows 4 feet tall.