There are few betterfor than gladioli but they must be planted in well-drained soil that does not dry out too readily in summer. This point is of fundamental importance as when a drought arrives and the soil is bone dry, flower spikes will be shorter and the individual rather smaller. Peat and will help to conserve moisture. Bonemeal may also be worked into the surface soil at the rate of 4 oz. per sq. yd. Peat, hop manure or compost will act as a surface mulch during a dry summer.
During a drought, if possible, wait until the flower can be actually felt in theand then water copiously at weekly intervals. The surface soil should be hoed a day later to prevent the ground ‘caking’. The best sizes to plant are 12/14 corms. Planting at intervals of 10—14 days from early March to mid-May will furnish blooms from July to the end of September. Flowering begins about 13 weeks after planting although this varies a little depending on variety, soil and district. Straight lines of gladioli look too stiff and formal and it is best to interplant with summer bedding subjects such as antirrhinums and pentstemons. They are also very effective planted in in a herbaceous border.
On heavy land plant about 3 in. deep, 4—6 in. on light, sandy soil. These depths are greater than those sometimes advised but deeper planting means that the plants suffer less in a drought and it may be possible to dispense with support, especially on heavy ground. The primulinus varieties do not usually require staking but the large-flowered varieties are often the better for some support to prevent the massive spikes being damaged by high winds, particularly in exposed positions. Stakes can be inserted just before the bottom florets start to open. They should go about 3 in. from the base of the plant to avoid injuring the. Give two ties, one just below the bottom bud, the other near the top of the stake.
The corms may be spaced 6 in. apart for gardenand cutting, up to 1 ft. apart for exhibition. are not reliably hardy and should be lifted as soon as the foliage turns yellow — usually during October. The old withered corm is discarded and the new plump corm or corms retained. Store in a cool, dry shed (which must be frostproof). A warm, dry shed or room (especially a room with any form of heating) will cause the corms to shrivel.
Gladioli are divided into several groups and the characteristics of each group are described, followed by descriptions of recommended varieties. A very wide selection is included to cover the extensive colour range of modern gladioli.
Large-flowered Varieties. The most popular type, usually 3% to 4,/2 ft high with stoutand 14 to 20 flowers on a spike. They are widely grown for exhibition and varieties especially suitable for this purpose are noted.
Abu Hassan: deep violet-blue with many flowers opening at the same time. One of the first varieties to bloom.
Antarctic: milky-white. Useful for exhibition.
Arabian Night: mahogany-brown.
Aranjuez: orange-apricot. Excellent for cutting.
Ardent: fiery red and salmon. Very vigorous with 20 blooms to a spike.
Beauties’ Blush: blush-pink. Useful for exhibition.
Black Jack: brownish-black.
Bow Bells: ruffled flowers, pink like the colour of the first of all the hybrid tea roses — La France. Very early.
Burma: rose-purple. Huge ruffled flowers. Not at its best in very hot sun or during rainy weather, but still first-rate for exhibition.
Caballero: a mixture of red, yellow and orange with scarlet blotches.
Circe: tangerine, crimson and cream. Flowers star-shaped.
Br Fleming: light salmon-pink with a cream throat. Useful for exhibition, as many as 10 flowers opening at the same time.
Evangeline: huge light pink flowers with a primrose throat. Excellent for exhibition.
Firebrand: orange-scarlet with a velvety sheen and a white line on the lower petals. Open blooms reflex like lily-flowered tulips. Another first-rate variety for exhibition.
Flower Song: deep yellow.
Greenland: deep cream with a greenish sheen.
Heirloom: huge lavender, ruffled flowers.
Hopman’s Glory: lemon-yellow.
Kaleidoscope: salmon, chestnut, purple and yellow. A glorious mixture of colours. Most unusual for indoor decoration.
Leif Erickson: cream. Excellent for exhibition.
Manchu: yellow flushed pink with a red blotch on the lower petals.
Up to 8 flowers open at a time.
Mansoer: dark mahogany-red.
Maria Goretti: pure white.
New Europe: light geranium-red. Late.
Patrol: apricot-yellow with as many as 12 flowers open at the same time. Veryto exhibition standard.
Pfitzer’s Sensation: deep violet-blue.
Picardy: creamy salmon-pink. An old variety but still valuable for garden, cutting and exhibition.
Pinnacle: Dark red. Florets up to 6 ½ m- across. Excellent for exhibition.
Salmon Queen: rich salmon with a creamy throat.
Salman’s Sensation: violet-blue. Snow Princess: milky-white. Increases very rapidly. Skylark: orange with a light gold throat.
Spic and Span: ruffled deep pink. Resistant to drought. Excellent for exhibition.
Tintoretto: lobelia-blue with cream and blue blotch. Uhu: ash-grey, salmon, mahogany-brown and yellow. Another multicolour which makes a striking cut flower. Victory Day: salmon-pink and cream. Winston Churchill: blood-red. Yellow Herald: golden-yellow. Early.
These are a smaller, more refined type of flower with hooded upper petals. They are very popular for cutting. The colour range has been widened considerably in recent years.
Atom: scarlet with a white picotee edge.
Blossomtime: rose-pink with cream throat.
Copernicus: coppery-orange with 5 to 6 flowers open at the same time.
Firelight: light salmon-orange with a cream throat.
Hokus Pokus: yellow and carmine.
Ivory Queen: ivory-white and mauve.
J. S. Peacock: salmon, flecked mahogany with crimson throat markings.
Lavender and Gold: the name describes the colours.
Matador: vivid crimson-scarlet.
Mother Unwin: smoky-salmon with helio flecks and a creamy throat.
Orange Prince: warm orange with a yellow throat.
Pamela Mummery: biscuity-salmon with creamy throat. A warm colour combination which usually makes an instant appeal to anyone seeing this variety for the first time.
Pegasus: creamy-white and carmine.
Richard Unwin: chestnut-crimson with cream stripes.
Strawberry Rival: strawberry-salmon with gold lines.
Vuurbaak: dark red.
White Lady: Pure white.
Varieties in this group grow to about 3 ft, with ruffled blooms, informally placed on the spike and varying from 2 to 3Y2 in- across. The colours are very warm and lively and the cut spikes lend themselves readily to unusual flower.
Bo-Peep: buff-pink with creamy-yellow throat, stippled red.
Gremlin: scarlet and white.
Peter Pan: bright orange.
Pirouette: deep salmon.
Statuette: yellow with mauvy-red throat markings.
Gladioli in this group bear 6 to 8 open, dainty blooms about half the size of the large-flowered varieties and with waved and fluffy petals of great substance. The throat markings and blotches are reminiscent of some butterflies. They grow to about 3 ft.
Attica: soft pink.
Cassandra: salmon-red, large yellow blotch with white stripes.
Green Woodpecker: sulphur-green with red throat.
Melodie: light pink with orange-scarlet blotches.
Rendezvous: rich orange-scarlet.
Vivaldi: burnt orange.
Walt Disney: primrose with red throat.
Much hybridising has taken place between the various sections and the differences may not be clear to the beginner. Catalogues of bulb specialists should be consulted regarding the latest developments. The early-flowering varieties bear relatively small spikes and individual blooms but are usually very graceful. They bloom mostly in May and June. They are not hardy and if planted outdoors must be grown on a warm, sheltered border and protected from severe frosts with loose straw, bracken or similar material. Market growers force these types under glass for early blooms. They may be potted in late October and grown on in a frost-proof, allowing 4 corms to a 6 in. pot. The vermilion-scarlet Spitfire, the orange-scarlet Brilliant and the aptly-named Peach Blossom are good varieties.
Pests and Diseases of Gladioli:
thrips are a comparatively new insect pest, and were not recorded in the British Isles until 1950. Damaged flowers are mottled, foliage turns a silvery or brown colour and infested corms show a rough, brown appearance. A BHC emulsion may be used in early summer, when the plants are about 6 in. high and repeated as necessary. After lifting the corms remove all loose scale leaves (the over-wintering female thrips beneath these scales) and dust with a 5 per cent Pyrethrin .
There are several fungus diseases which persist oncorms and thus continue from year to year unless steps are taken to control infection. For example, dry rot is denoted by yellowing of the foliage and black markings on the corms. Although infected corms are best discarded it is possible to dip corms in a mercurial fungicide such as ‘Aretan’ to prevent attacks.
Propagation of Gladioli:
The cormlets or ‘spawn’ found at the base of the old corms can be saved, stored separately, planted in deepboxes which should be kept slightly moist. They take 2 or 3 years to bloom after planting outside, lifting and storing in the usual way. This may sound a little tedious but most varieties (especially in the primu-linus group) produce large numbers of cormlets so that once is started a large stock of a favourite variety can eventually be obtained.