Tropaeolum majus

Description

It is a fast-growing plant, either annual or perennial, with trailing stems growing to 3-6 ft. The leaves are large, nearly circular, 3 to 15 cm in diameter, green to glaucous green above, paler below; they are peltate, with the 5–30-cm-long petiole near the middle of the leaf, with several veins radiating to the smoothly rounded or slightly lobed margin.

The flowers are 2.5–6 cm in diameter, mildly scented, with five petals, eight stamens, and a 2.5–3-cm-long nectar spur at the rear. The petals vary from yellow to orange to red, frilled and often darker at the base. The fruit is 2 cm broad, three-segmented, each segment with a single large seed 1–1.5 cm long.

|TropaeolumMajusOrange.jpg|Botanical scan |Tropaeolum majus 02 ies.jpg|Underside of leaf |Yellow and red Tropaeolum majus (Garden nasturtium).jpg|Leaves and flowers |TropaeolumMajusVariety.jpg|Some color varieties |Kapuziner-Kresse 7148.jpg|Flower showing nectar spur |Tropaeolum majus 04 ies.jpg|Flower cut through to show structure |Tropaeolum majus0.jpg|Immature fruit

Unique effects

Nasturtium leaves, like some other species, demonstrate the lotus effect, whereby rainwater falling on the surface gathers into globular droplets which roll off the leaf, leaving it dry and clean.

Das Elisabeth Linné-Phänomen (the Elizabeth Linnæus Phenomenon), named after Carl Linnaeus's daughter Elisabeth Christina von Linné (who discovered the phenomenon at age 19) refers to the appearance of 'flashing' flowers. Especially at dusk, the orange flowers may appear to emit small flashes. Once believed to be an electrical effect, it is today thought to be an optical reaction in the human eye caused by the contrast between the orange flowers and the surrounding green.

Etymology

The species was originally called Nasturtium indicum ("Indian nasturtium") but the plant is not related to the true Nasturtium genus.

The current genus name Tropaeolum, coined by Linnaeus, means "little trophy". Tropaeolum is the diminutive form of the Latin tropaeum, itself borrowed from Ancient Greek τρόπαιον : trópaion "trophy".

The Latin specific epithet majus means "larger" (the neuter form of major).

Distribution and habitat

The species is of cultivated, probably hybrid origin. It originated in the Andes from Bolivia north to Colombia.

The species has become naturalized in parts of the United States (California, New York, Pennsylvania, New Hampshire, Massachusetts, Connecticut and Virginia), as well as parts of Europe and Asia, Africa and Australia. It is listed as invasive in Hawaii and Lord Howe Island, Australia.

Ecology

The garden nasturtium is used as a food plant by the larvae of some lepidopteran species including the dot moth, the garden carpet moth and the large white or cabbage white butterfly.

Cultivation

Tropaeolum majus cultivars are widely grown as easy annual plants, and will grow in poor, damp soil in full sun. The large seeds are easy to handle individually.

As they do not tolerate heavy frost, in cooler climates they are best sown under glass in heat, and planted out after all danger of frost has passed. Alternatively, as they are fast-growing, they may be sown in situ after that time.

Many flower colours are available, in the warm spectrum from cream through yellow, orange, red and maroon. Some have highly decorative marbling on the leaves.

The groups Whirlybird Series{{cite web | url = https://www.rhs.org.uk/Plants/106276/i-Tropaeolum-majus-i-Whirlybird-Series/Details

Uses

All of the above-ground parts of the plants are edible. The flower has most often been consumed, making for an especially ornamental salad ingredient; it has a slightly peppery taste reminiscent of watercress, and is also used in stir fry. The flowers contain about 130 mg vitamin C per 100 g, about the same amount as is contained in parsley. Moreover, they contain up to 45 mg of lutein per 100 g, which is the highest amount found in any edible plant. The unripe seed pods can be harvested and dropped into spiced vinegar to become a condiment and garnish, sometimes used in place of capers.

Some native South Americans used the plant medicinally, apparently due to its antibiotic (including antibacterial) properties. Some Europeans ate it to treat urinary and genital infections.

|P7024519ナスタチウムサラダ.jpg|Salad with flowers and leaves |Nasturtium Seeds.jpg|Seed pods

References

References

1. [http://www.tropicos.org/Name/33000034?tab=synonyms Tropicos]
2. [http://www.theplantlist.org/tpl1.1/record/kew-2522052 The Plant List]
3. {{GRIN
4. (11 July 2013). "''Tropaeolum majus''". Institute of Pacific Islands Forestry.
5. [https://pfaf.org/user/plant.aspx?LatinName=Tropaeolum+majus Tropaeolum majus - L.] [[Plants For A Future]]
6. Jepson Flora: [http://ucjeps.berkeley.edu/cgi-bin/get_JM_treatment.pl?Tropaeolum+majus ''Tropaeolum majus'']
7. Pacific Island Ecosystems at Risk: [http://www.hear.org/pier/species/tropaeolum_majus.htm ''Tropaeolum majus'']
8. "Scientific Image - Water Droplet on a Nasturtium Leaf". [[NISE]] (National informal stem education network).
9. H. W. "[http://www.nature.com/nature/journal/v93/n2327/abs/093348a0.html Das Elisabeth Linné-Phänomen (sogenanntes Blitzen der Blüten) und seine Deutungen]", ''[[Nature (journal). Nature]]'' (nature.com). Retrieved 4 May 2013.
10. "[https://sverigesradio.se/sida/avsnitt/185578?programid=1667 Försenad jätteplantering till Malmös schlagerfest, expert varnar för kalkning och kogödsel på påse]", ''Odla med P1'', [[Sveriges Radio]], 29 April 2013. Retrieved 4 May 2013. (in Swedish)
11. Harrison, Lorraine. (2012). "RHS Latin for Gardeners". Mitchell Beazley.
12. Huxley, A., ed. (1992). ''New RHS Dictionary of Gardening''. Macmillan {{ISBN. 0-333-47494-5.
13. [http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=200012407 Flora of North America v 7 p 166]
14. "Plants Profile for ''Tropaeolum majus'' (nasturtium)".
15. "Dot Moth - ''Melanchra persicariae''". NatureSpot.
16. Plymley, Katherine. "Garden Carpet Moth and Caterpillar ''Xanthorhoe fluctuata'', Nasturtium". Shrewsbury Museums Service.
17. (2011-02-22). "Cabbage caterpillars". Royal Horticultural Society.
18. "RHS Plantfinder - ''Tropaeolum majus'' Alaska Series".
19. (July 2017). "AGM Plants - Ornamental". Royal Horticultural Society.
20. (2016). "Foraging Wild Edible Plants of North America: More than 150 Delicious Recipes Using Nature's Edibles". Rowman & Littlefield.
21. "''Tropaeolum minus''". Plants For A Future.
22. United States Department of Agriculture Research Service. (2010). "USDA National Nutrient Database for Standard Reference, Release 23". Nutrient Data Laboratory.
23. (2005). "Flowers and Leaves of ''Tropaeolum majus'' L. as Rich Sources of Lutein". Journal of Food Science.
24. Owen, Marion. "Poor Man's Capers: How to make gourmet capers from nasturtium seed pods".
25. Lyle, Katie Letcher. (2010). "The Complete Guide to Edible Wild Plants, Mushrooms, Fruits, and Nuts: How to Find, Identify, and Cook Them". [[FalconGuides]].