Gladiolus

These popular plants can be used to provide quite an impressive impact in the border, with their tall, brilliantly coloured flower spikes. Very popular as cut flowers.

Family: Iridaceae (iris)
Botanical Name: Gladiolus
Common Names: Sword Lily

Foliage: Fans of sword-shaped green leaves. Deciduous (dies back after flowering).

Flowers: Tall flower spikes, lined with showy funnel-shaped flowers. Each bloom can be as much as 4 inches (10cm) across. Wide range of colours and hues available.

Flowering Period: Mid to late Summer.

Soil: Fertile well-drained soil (sand, chalk, loam), any pH.

Conditions: Best in full sun, in a south, east or west facing aspect, in a sheltered location.

Habit: Tall, bushy.

Type: Cormous perennial.

Origin: Africa, Mediterranean and southern Europe to central Asia.

Hardiness: Hardy in warmer and coastal regions of the UK (down to -5°C)

Planting and Growing Gladiolus

Plant corms in spring in the border or in pots and containers. If the soil is not well drained, plant on a bed of sand or sharp grit.

Choose and open sunny position in a loam or sandy soil, enrich light and heavy clays with plenty of organic matter.

The flowering season can be short lived, especially if the weather is very hot, so either plant them in amongst other later flowering plants, use succession planting (every two weeks) to extend the season, or plant in pots and move them out of the way once the flowers have faded.

A good choice for coastal gardens. Copes well in dry conditions. Excellent as cut flowers.

Taking Care of Gladiolus

Feed with a potassium-rich fertiliser once flower spikes appear.

Stake tall varieties in exposed sights.

Lift the corms once the leaves have died back in the autumn. Dry off and keep in a frost-free environment, ready for replanting in the spring. In milder areas the corms can be left in the ground to naturalise. Although, very cold winters can still kill off these semi-hardy plants if left in the ground.

Pruning Gladiolus

Not necessary. Remove the old stems from the corms after lifting.

Pests and Diseases

Susceptible to attack by thrips, aphids and slugs. Can be affected by corm rot and grey mould (botrytis).

Propagating Gladiolus

Sow seed in Spring or lift established corms and replant the tiny corms (cormlets), that appear around the base. For details see Propagating Bulbs, Corms and Tubers.

Popular Varieties of Gladiolus Available in the UK

Most of the popular gladioli available in garden centres are half-hardy hybrids. They vary in
flower-size and form and include flowers of virtually every colour. They are classified into several main groups:

Large-flowered: this is the most popular group, with tall spikes of wide open blooms. Height to 4ft (1.2m).

Miniature: smaller and neater, including the slightly larger Butterfly strain. Height to 3ft (90cm).

Primulinus: similar in size and form to Miniatures, but each flower has a hooded upper petal.

Species Include:

G. byzantinus has green sword-shaped leaves topped with firm spikes of magenta trumpet flowers from late spring. Height 2ft (60cm). One of the hardiest forms. Available at You Garden.

G. murielae (Abyssinian Gladioli, Acidanthera, Peacock Orchid, Gladiolus callianthus) is a more dainty form with richly scented white flowers that have a dark centre. Height to 3ft (90cm). Half-hardy in the UK. Available at Thompson and Morgan.

G. nanus is shorter growing variety, available in a range of colours, ideal for containers. Height to 1ft (30cm).

Gladioli Hybrids Include:

G. 'Black Surprise' is a deep purple, almost black flowering variety. Height to 2ft (60cm).

G. 'Brown Sugar' has tall flower spikes of burnt orange. Height to 2ft (60cm).

G. 'Green Star' is a tall variety with unusual bright green flower spikes. Height to 3ft (90cm). Available at Thompson and Morgan.

G. 'Limoncello' has magnificent large yellow blooms on strong upright stems. Height to 2ft (60cm). Available at Thompson and Morgan.

G. nanus 'lipstick' compact, short stemmed Gladioli in shades of pink, red and white. Height to 18in (45cm). Available at You Garden.

G. nanus 'Robinetta' a dwarf form that produces short spikes of plentiful pinkish red flowers with dainty white markings. Early summer flowering. Height from 18 to 24in (45- 60cm).

G. 'Tango' provides a fabulous sight with exotic ruffled, mauve/pink blooms, on stiff upright stems. Height to 2ft (60cm). Available at Thompson and Morgan.

Plant Groups