Stately spikes of gladioli (Gladiolus spp.) are the classic choice for fresh-flower arrangements.
This elegant beauty blooms in warm shades of pink, salmon, yellow, red; cool tints of lilac and lavender-blue; and peaceful white. Blooms open from bottom to top with petals that are frilled, ruffled, semi-ruffled, or plain. Glads are grouped by flower size from miniature to giant. The larger ones are most popular with florists. While most glads are hardy to Zone 7 as a perennial, one (Gladiolus nanus) is hardy to Zone 5.
 

Plant Facts
Common name: Gladiolus, sword lily
Botanical name: Gladiolus spp.
Plant type: Corm
Height: 3 to 60 inches tall
Zones: Hardy Zones 7 to 10 as a perennial (possibly Zone 6 with several inches of loose mulch during winter) for most varieties. Annual in Zones 3 to 10.
Family: Iridaceae (Iris)

Growing conditions

  • Sun: Full sun
  • Soil: Glads grow in a variety of soils, but loam or sandy loam gives best results. Good drainage is imperative.
  • Moisture: 1 inch of water a week.


Care

  • Mulch: Apply a 2- to 4-inch layer of organic mulch to help prevent weeds and conserve moisture.
  • Fertilizer: Add a balanced fertilizer to soil before planting. Apply fertilizer higher in potash when growth is 1/3 of final height. Keep fertilizer away from plant stems.
  • Pruning: Remove spent blooms.


Cultivars

  • ‘Mon Amour' (pictured) has flowers with pink and yellow highlights in midsummer to early fall. Grows 36 to 48 inches tall.
  • ‘Green Star' has lime-green flowers in midsummer to early fall. Grows 36 to 48 inches tall.
  • ‘Parade' has ruffled salmon-pink flowers in late summer. Flower spikes grow 32 to 34 inches tall.
  • ‘Pulchritude' has ruffled lavender-pink flowers with red marks. An early season bloomer, the flower spikes grow 30 inches tall.
  • ‘Sunsport' has ruffled ivory and deep yellow flowers from late spring to early fall. Flower spikes grow 26 to 28 inches tall.
  • ‘Zephyr' has ruffled, light lavender to pink flowers with cream-colored centers. It blooms late spring to early fall. Flower spikes grow 32 inches tall.

Garden notes

  • Purchase firm, plump, high-centered corms with smooth husks and no spots or dark areas.
  • Plant corms 3 to 6 inches deep and 3 to 6 inches apart in spring, depending on size of corms.
  • Plant in clumps of seven or more in a perennial garden or in rows in a cutting garden.
  • Plant a variety of cultivars in two-week intervals to achieve a longer bloom period. Some glads bloom late spring to early fall (Grandiflorus group); some early summer (Nanus group); and others early to late summer (Primulinus group).
  • Stake tallest cultivars to keep them from falling.
  • Where treated as an annual, lift corms six weeks after blooming, then cut foliage, shake off soil, and dry for a couple of weeks. Select best new corms and store in a dry, frost-free place. Discard old corms.

Pests

  • Corm rot, stem rot, gray mold, viruses, and aster yellows may occur.
  • Mites, thrips, and aphids may attack

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Propagation

  • Separate cormlets when dormant.


All in the family

  • The Iridaceae (Iris) family includes perennials with showy flowers and long narrow leaves such as crocus, iris, freesia, tiger flower, and crocosmia.

Text by Mary Pestel, photo courtesy of Dutch Gardens, www.dutchgardens.com.