Pronounciation: Gla-dee-OL-us hor-tul-A-nus

Hardiness zones:
Sunset 2-24
USDA 3-11

Landscape Use: Floral accent, mesic mixed garden borders, patio containers, pollinator gardens, nostalgic gardens, heritage gardens, gardens dedicated to grandmas of the 20^th century, cut flowers.

Form & Character: Upright, colorful, fleeting, lovely, delicate, ephemeral.

Growth Habit: Deciduous to semi-evergreen herbaceous perennial, clumping, produces corms, stems acaulescent, unbranched, upright from 12-inches to 2-feet tall, floral scapes or spikes upright to 4-feet tall.

Foliage/Texture: Generally 1 to 9 narrow, acuminate narrowly-lanceolate, sessile leaves from 12-inches to 2-feet long, longitudinally grooved, dull to glaucous green, basal, enclosed in a sheath, leaf blades generally in a plane or cruciform in cross section, the lowest leaf is shortened to a cataphyll; medium coarse texture.

Flowers & Fruits: Flowers grow 'one-sided' on elongated spikes, individual flowers are bisexual each subtended by two leathery, green bracts. Flower sepals and the petals (called tepals) are almost identical in appearance, united at their base into a tube-shaped structure, dorsal tepal is the largest, arching over the three stamens, other tepals are narrower, flower perianth is funnel-shaped with the stamens attached to its base. Flowers are variously colored ranging from white, cream white, yellow, pink, orange, red to light purple with contrasting white markings; fruits are oblong or globose capsules each with a 3-locular ovary containing many winged, brown, longitudinally dehiscent seeds.

Seasonal Color: Flowering accents range from spring to summer depending on elevation and location, spring in lower desert gardens (aka Phoenix or Tucson), summer in higher elevation landscape gardens (aka Williams or Flagstaff).

Temperature: Generally Phoenix cold hardy, but intolerant of temperatures higher than 105^oF.

Light: Partial to full sun, no full shade.

Soil: Perfers a richly-amended, well-drained garden soil.

Watering: Occasional supplemental water is needed during the winter and spring depending on frequency of winter rains, otherwise regular garden watering.

Pruning: Generally no pruning required unless grown for cut flowers.

Propagation: Extremely easy by division of corms, otherwise nursery propagators will use tissue culture techniques to prevent virus propagation.

Disease and Pests: Common gladiolus diseases include botrytis, crown rot, rust, wilt and mosaic virus. Common gladiolus pests include aphids, mealy bugs, spider mites and thrips. Disease and pest pressures in Arizona landscape gardens are lessened by relatively drier climate conditions.

Additional comments: Hybrid gladioli are a much-cherished, old-fashioned garden perennial that because of desert heat sensitivies are generally cultured as cool season annuals; although in mesic areas of Phoenix (think Arcadia) gladioli corms can be left in place, treated as short-lived deciduous perennials, and dug and divided in late spring to early summer every few years. If grown as an annual, purchase corms during late summer or early fall to plant in rich garden soil during October. Gladioli corms are best planted at a soil depth of 6 inches in groups at a spacing distance of 6 inches. In lower desert gardens, gladioli flowers are generally an Easter decoration mainstay.

Hybrid gladious can be divided into three main groups:

1. Grandiflora hybrids - grow large funnel-shaped flowers, 4- to 6-inches wide on 3- to 6-feet tall spikes or scapes, up to 30 flowers per spike. Extensive range of flower colors. Grandiflora hybrids are considered by many to be the most difficult group to culture in typical garden settings because of their size and tendency to flop.
2. Nanus hybrids - miniature hybrids with small flaring blooms reaching up to 3-inches wide on 1.5-feet tall scapes.
3. Primulinus hybrids - grow hooded-type flowers that are held loosely on 2- to 4-feet tall scapes. Butterfly hybrids, a subgroup of the Primulinus hybrids, grow flowers with ruffled petals and contrasting throat blotches and other markings on 2- to 3-feet tall scapes.