Tropaeolum majus

Tropaeolum is a genus of about 80 species of annuals and perennials native to South/Central America. The common Nasturtium (Tropaeolum majus) is the most frequently found member of the family. 

Nasturtium is from the latin words meaning literally “nose-twister” or “nose-tweaker” (referring to the pungent smell of some species!). The Tropaeolum Nasturtiums received their common name because they produce an oil that is similar to that produced by watercress (Nasturtium officinale).

Tropaeolum peregrinum

Tropaeolum includes several very popular garden plants, the most commonly grown being T. majus T. peregrinum and T. speciosum.  The hardiest species is T. polyphyllum from Chile, the perennial roots of which can survive underground when air temperatures drop as low as −15 °C (5 °F).

Plants in this genus have showy, often intensely bright flowers (in reds, oranges and yellows), and rounded, shield- shaped leaves which vary in colour and include some attractive blue – green tones. Flowers have five petals (sometimes more) and a funnel-shaped nectar tube at the back. The name Tropaeolum is from the Latin tropaeum , meaning ‘trophy’ and was originally chosen by the swedish botanist Carl Linnaeus in the 18th century.

After victory in battle, the Romans used to set up a trophy pole called a tropaeum (from the Greek tropaion, source of the English word ‘trophy’). On this the armour and weapons of the vanquished foe were hung. Linnaeus was reminded of this by the plant as the round leaves resemble shields and the flowers, blood-stained helmets.

Tropaeolums in a border

Species names of Tropaeolum include:

T. aduncum = hooked (the flowers)

T. canariense = canary – referring to the colour and shape of the flowers (the ‘Canary Creeper’)

T. lobbianum =  after Lobb the plant collector

T. majus = great (the Climbing Nasturtium)

T. minus = small (the Dwarf Nasturtium)

T. pentaphyllum = five leaved or divided into five

T. pergrinum = foreign or wandering, probably referring to its straggly growth

T. speciosum = showy

T. tuberosum = tuberous

‘Canary Creeper’ (T. canariense)

Nasturtiums were also known as “Indian cress”. This derived from their use as a salad ingredient and because at that time South/Central America was referred to as ‘the Indies’. The 16th-century herbalist John Gerard called the plant “Lark’s Heel”, referring to the flower’s spur (and similar to Larkspur).

All parts of T. majus are edible. The flower is most often eaten as an ornamental salad ingredient or in a stir fry; it has a slightly peppery taste reminiscent of watercress. The flowers contain about 130 milligrams of Vitamin C per 100 grams or about the same amount as in Parsley. The unripe seed pods can be harvested and dropped into spiced vinegar to produce a condiment and garnish, sometimes used in place of capers.

Tropaeolum leaves and flowers as salad ingredients

Nasturtiums have been used in herbal medicines for their antiseptic and expectorant qualities. They are said to be good for a chest cold and to promote well being by the formation of new blood cells. The common Nasturtium has been used in herbal medicine for respiratory and urinary tract infections.

The bright, quaintly – shaped flowers are usually freely produced on long stalks, and the fast growth of many of the climbers makes the Tropaeolum a very useful, decorative plant. They will spill beautifully over walls and onto paths, when used as edging plants. They also hold up very well in containers. Climbing varieties, such as ‘Canary Creeper’ will amble up and through shrubs. Bushy, ground hugging plants will fill in gaps among complementary – coloured day lilies and roses.

You can use clusters of plants to brighten up the vegetable garden – and to act as ‘sacrificial’ ‘plants to attract caterpillars away from your brassicas!

Sources and further information:

Wikipedia

Tropaeolum speciosum

Growing Tropaeolum

Tropaeolum varieties

Quizzicals: two cryptic clues to flower, plant, veg or fruit names –

• Bird swearing
• Vasectomy for Dad

(thanks to Les Palmer, answers in the next Plantax!)

Old School Gardener

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