Wavy Gladiolus

Gladiolus undulatus L.

Synonyms - Gladiolus cuspidatus.

Order: Liliales

Family: Iridaceae

Names:

Gladiolus is from the Latin gladiolus meaning a small sword and refers to the leaf shape.
Undulatus means wavy or undulating and refers to the wavy petals of the flower.

Other Names:

Wild Gladiolus.

Summary:

Wavy Gladiolus is a tufted herb with 3-5 erect sword-shaped leaves with red- purple sheaths arising annually from a corm. The erect flower spike is often more than 1 m high and has one sided sprays of 3-8, showy, white to cream flowers, sometimes with a tinge of green or pink. The funnel shaped flowers are 11.5-14.5 cm long with 6 pointed petal lobes 5-7 cm long and have a distinctive wavy margin. It has 3 stamens with purple anthers and a 3-branched style. The underground egg-shaped corm is 15-30 mm diameter with a brown fibrous covering and sits above many small cormels.
Wavy Gladiolus occurs commonly along roadsides and watercourses in wetter areas. It is native to South Africa and flowers from spring to early summer.

Description:

Cotyledons:

Two.

First leaves:

Leaves:

3-5 basal leaves with red-purple sheaths in 2 rows on either side of the stem overlapping at the base.
Blade - Sword shaped, strap like, flat, hairless, rigid, ribbed, 250-1500 mm long x 8-20 mm wide, green and often tinged with purple. Folded lengthwise to join along the edges at the base where it clasps the leaf on the other side of the stem.
Sheath - Red-purple, tightly hugging the stem.
Stem leaves - Small and bract like.

Stems:

Flower stem - Erect, slightly longer than the leaves, 500-1500 mm tall.

Flower head:

Loose groups of 3-12 single, stalkless flowers borne on one side at the end of the stem in a spike. Large, papery, green or brown lance shaped outer bract, 40-70 mm long and a 30-40 mm long inner bract under the flowers.

Flowers:

Cream or green.
Ovary - Style slender and cylindrical. Style branches narrowly egg shaped, about 8 mm long, undivided, folded lengthwise, parallel sided with a notched tip.
Perianth - Cream or green, sometimes tinged with pink, 60-80 mm long. Very narrow, slightly curved or straight, tubular lower part and a normally funnel shaped upper part with 6 lobes. The lobes have wavy edges, are lance shaped with long slender tips and have a greenish white tinge on the lower half. The upper lobes are 55-70 mm long x 12-17 mm wide and the lower ones 40-60 mm long x 9-12 mm wide. The lower lobes often have a dark green to purple line down the middle extending into the tube.
Stamens - Bent, attached at the top of the narrow part of the floral tube. Filaments free.
Anthers - Purple, attached at the base, about 7-8 mm long and much shorter than the filaments.

Fruit:

Globular to cylindric capsule but this has not been seen in WA or NZ.

Seeds:

None in WA.

Roots:

Globular to egg shaped corm, 15-30 mm diameter, with a brown fibrous covering. Numerous brown cormels are often present beneath the corm.

Key Characters:

Basal leaves 3-5, parallel veined.
Leaf blade at least 8 mm wide, flat, glabrous.
Leaf sheath glabrous or sparsely minutely hairy.
1 sessile flower in each spathe.
Floral bracts green or brown, herbaceous, entire or emarginate (shallowly notched)
Perianth tube narrow and cylindrical in the lower part to funnel shaped in the upper part, 65-75 mm long.
Perianth lobes acuminate, 40-70 mm long, with a long tapering undulate tip.
Style branches egg shaped or minutely tricuspidate.
3 purple anthers, 3-8 mm long.
Ovary inferior.
Adapted from John Black and Gillian Perry.

Biology:

Life cycle:

Annual leaves, stems and flowers with a perennial corm. Cormels are planted in late spring to produce corms for planting. Flowers harvested when in the tight bud stage with the lower florets just showing colour, which is 70-140 days after planting. 3-4 leaves are left on the plant to develop the new corm. Corms are dug 4-6 weeks after harvest, cleaned, cured and stored at 3-70C for more than 6 weeks before replanting.

Physiology:

Sensitive to frost.
Sensitive to drought.
Sensitive to wind.

Reproduction:

By corms and cormels.

Flowering times:

October to December in WA.
December to February in SA.
November to January in SE Australia.
December in New Zealand.

Seed Biology and Germination:

No seed produced in WA or NZ.

Vegetative Propagules:

Corm and cormels.

Hybrids:

None.

Allelopathy:

Population Dynamics and Dispersal:

Spread by corms and cormels in garden refuse and soil from earthmoving. Many tiny cormels spread by water flows.

Origin and History:

South Africa south western Cape Province.
Introduced as an ornamental.

Distribution:

ACT, NSW, SA, TAS, VIC, WA.

Courtesy Australia's Virtual Herbarium.

Habitats:

Climate:

Temperate. Mediterranean.

Soil:

Prefers wet areas.

Plant Associations:

Significance:

Beneficial:

Cultivated ornamental.

Detrimental:

Weed of roadsides, waterways, damp areas, under grazed wet pastures, beaches and disturbed bushland.

Toxicity:

Not recorded as toxic.

Legislation:

None.

Management and Control:

Planted at 150,000-225,000 corms/ha in commercial gardens.
Grazing and or cultivation usually provide control.

Thresholds:

Eradication strategies:

These plants are very difficult to control by hand weeding because they produce many small cormels under the main corm. Dig up the plant and soil containing the corm and many cormels. Burn the soil, soak in diesel or bury more than 1 metre deep.
Wipe leaves with a mixture of 1 L glyphosate (450g/L) plus 2 L water or Spray with 100 mL glyphosate(450g/L) in 10 L of water before flowering in late winter to early spring. The area will require spraying again next season to control the tiny seedlings emerging from cormels. 20 g/ha metsulfuron(600g/kg) or 0.2 g plus 25 mL Pulse® in 10 L water also provides good control with little effect on grasses.
Grazing and mowing can provide control after a few years.
Replant native shrub species if necessary. Avoid earth works that carry new cormels into the area. Start control at the top of the catchment to prevent water-transported cormels reinfesting treated areas.

Herbicide resistance:

Biological Control:

Gladiolus are sensitive to disease and fumigation is usually necessary, in commercial gardens, where Gladiolus has been grown previously.
Sensitive to thrips, Helicoverpa, and Cluster Grubs.
Sensitive to Botrytis, Curvularia, Fusarium, Septoria, Stromatinia, Bacterial scab, Bean Yellow Mosaic Virus and Cucumber Mosaic Virus.

Related plants:

Byzantine Gladiolus (Gladiolus communis ssp. byzantinus = Gladiolus illyricus)
Large-flowered Gladiolus (Gladiolus tristis = Gladiolus longicollis)
Long-tubed Painted Lady (Gladiolus angustus)
Pink Gladiolus (Gladiolus communis)
Wavy Gladiolus (Gladiolus undulatus) flowers later than most other species.
Wild Gladiolus (Gladiolus caryophyllaceus)
Gladiolus alatus
Gladiolus cardinalis
Gladiolus carneus
Gladiolus floribundus
Gladiolus gueinzii

Plants of similar appearance:

Babiana
Ixia
Chasmanthe
Crocosmia
Ferraria
Freesia
Moraea
Ornithogalum
Sparaxis
Tritonia
Watsonia

References:

Black, J.M. (1978). Flora of South Australia. (Government Printer, Adelaide, South Australia). P372. Diagram.

Bodkin, F. (1986). Encyclopaedia Botanica. (Angus and Robertson, Australia).

Blood, K. (2001). Environmental weeds: a field guide for SE Australia. (CH Jerram & Associates, Australia). P177. Photos.

Everist, S.L. (1974). Poisonous Plants of Australia. (Angus and Robertson, Sydney).

Harden, Gwen J. (1991). Flora of NSW. (Royal Botanic Gardens, Sydney). P. Diagram.

Hussey, B.M.J., Keighery, G.J., Cousens, R.D., Dodd, J. and Lloyd, S.G. (1997). Western Weeds. A guide to the weeds of Western Australia. (Plant Protection Society of Western Australia, Perth, Western Australia). P30.

Lamp, C. and Collet, F. (1990). A Field Guide to Weeds in Australia. (Inkata Press, Melbourne).

Lazarides, M. and Cowley, K. and Hohnen, P. (1997). CSIRO handbook of Australian Weeds. (CSIRO, Melbourne). #448.14.

Marchant et al (1987). Flora of the Perth Region. (Western Australian Herbarium, Department of Agriculture, Western Australia). P794.

McBarron, E.J. (1983). Poisonous plants. (Inkata Press, Melbourne).

Moore, J.H. and Wheeler, J.R. (2002). Southern Weeds and their Control. Photos.

Roy, B., Popay, I., Champion, P., James, T. and Rahman, A. (1998). An Illustrated Guide to Common Weeds of New Zealand. (New Zealand Plant Protection Society). P169. Photo

Reid, R.L. (1990) The Manual of Australian Agriculture. (Butterworths, Sydney). P210-211.

Acknowledgments:

Collated by HerbiGuide. Phone 08 98444064 or www.herbiguide.com.au for more information.