Springing into summer

Back in May there came botanical evidence that we were moving from spring into summer. In places with cold winters, it became possible to plant nasturtium seeds, because those places were moving past their last frost date. Meanwhile, here in Palo Alto, my geranium plants (in containers on my patios), which went through the winter as foliage plants, broke into bloom (as the cymbidium orchids moved into summer dormancy).

I’ve referred to these summer plants by their common names — as nasturtiums and geraniums — but their genus names are, respectively, Tropaeolum and Pelargonium. And to make things more confusing, there are genera (of different plants) Nasturtium (to which watercress belongs) and Geranium (the cranesbills).

Nasturtiums/Tropaeolum. These wonderfully cheery flowers are incredibly easy to grow. In fact, they’re a great plant for kids to grow from seed: the seeds are big and easy to handle, and a kid can just push one into the ground with a thumb, and then water regularly. The plants shoot up quickly and grow fast.

From Wikipedia:

Tropaeolum …, commonly known as Nasturtium (… literally “nose-twister” or “nose-tweaker”), is a genus of roughly 80 species of annual and perennial herbaceous flowering plants. It was named by Carl Linnaeus and is the only genus in the family Tropaeolaceae. The nasturtiums received their common name because they produce an oil that is similar to that produced by watercress (Nasturtium officinale).

The genus Tropaeolum, native to South and Central America, includes several very popular garden plants, the most commonly grown being T. majus, T. peregrinum and T. speciosum.

… Plants in this genus have showy, often intensely bright flowers, and rounded, peltate (shield-shaped) leaves with the petiole in the centre. The flowers have five petals (sometimes more), a three-carpelled ovary, and a funnel-shaped nectar tube at the back.

History: The first nasturtium species was introduced into Europe in the 18th century and was named Tropaeolum minus by the Swedish botanist Carl Linnaeus. He chose the genus name because the plant reminded him of an ancient custom. After victory in battle, the Romans used to set up a trophy pole called a tropaeum (from the Greek tropaion, source of English “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 resembled shields and the flowers, blood-stained helmets.

Nasturtiums were also known as “Indian cress”. This was because, when they were introduced they were used as a salad ingredient and they originated from South America which at that time was known as the Indies.

… Species in cultivation: The most common species in cultivation is a hybrid of T. majus, T. minus and T. peltophorum and is commonly just known as a nasturtium. It is mostly grown from seed as a half-hardy annual and both single and double varieties are available (doubles are mostly sterile and need to be propagated from cuttings). It comes in a range of habits and colours including cream, yellow, orange and red, either solid colour or striped and often with a dark blotch at the base of the petals. It is vigorous and easily grown and prefers a sunny spot. It thrives in poor soil and dry conditions whereas in rich soil it tends to produce much leafy growth and few flowers. Some varieties adopt a bush form while others scramble over and through other plants and are useful for planting in awkward spots or for covering fences and trellises.

… Culinary uses: All parts of T. majus 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 milligrams (2.0 gr) vitamin C per 100 grams (3.5 oz), about the same amount as is contained 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.

Some nasturtiums close up:


And some sprawling all over the place:


Here in California, nasturtiums can run amok. I’ve seen some that have climbed to the tops of telephone poles, and the foundation walls of my father and stepmother’s house in Arroyo Grande were threatened by the vigorous root systems of nasturtiums growing wild there — a fact that filled my dad with horror at the idea that people would plant these monsters intentionally (as we did in Columbus OH, where frost killed the plants off).

The genus Nasturtium. On Nasturtium officinale (watercress), see my recent posting on gay greens.

Geraniums/Pelargonium. From Wikipedia:

Pelargonium … is a genus of flowering plants which includes about 200 species of perennials, succulents, and shrubs, commonly known as geraniums (in the United States also storksbills). Confusingly, Geranium is the correct botanical name of a separate genus of related plants often called cranesbills or hardy geraniums. Both genera belong to the family Geraniaceae. Linnaeus originally included all the species in one genus, Geranium, but they were later separated into two genera by Charles L’Héritier in 1789.

Pelargonium species are evergreen perennials indigenous to Southern Africa, and are drought and heat tolerant, but can tolerate only minor frosts. They are extremely popular garden plants, grown as bedding plants in temperate regions.

… The name Pelargonium was introduced by Johannes Burman in 1738, from the Greek πελαργός, pelargós (stork), because the seed head looks like a stork’s beak.

… Scented-leaf pelargoniums: Cultivars are derived from a great number of species, amongst others P. graveolens. [There are a great many of these, some of which I grow here in Palo Alto. Strictly speaking, pelargoniums in general have strongly scented leaves, but the standard ones smell “like geraniums” rather than like roses, cinnamon, apples, or whatever.]

Nasturtiums and watercress share a name because of their shared sensory properties. Geraniums and cranesbills are actually botanically similar, though distinct, so the shared name makes sense in another way.

Three pelargonium photos: a single flower from a single-flowered rose pelargonium plant; a pot of fancy doubles; and four pots of fancy doubles in a different set of cultivars:




The genus Geranium. From Wikipedia:

Geranium is a genus of 422 species of flowering annual, biennial, and perennial plants that are commonly known as the cranesbills. They are found throughout the temperate regions of the world and the mountains of the tropics, but mostly in the eastern part of the Mediterranean region. The long, palmately cleft leaves are broadly circular in form. The flowers have five petals and are coloured white, pink, purple or blue, often with distinctive veining.

… The genus name is derived from the Greek γέρανος, géranos, or γερανός, geranós, crane. The English name “cranesbill” derives from the appearance of the fruit capsule of some of the species. Species in the Geranium genus have a distinctive mechanism for seed dispersal. This consists of a beak-like column which springs open when ripe and casts the seeds some distance. The fruit capsule consists of five cells, each containing one seed, joined to a column produced from the centre of the old flower. The common name cranesbill comes from the shape of the unsprung column, which in some species is long and looks like the bill of a crane.

… Confusingly, “geranium” is also the common name of members of the genus Pelargonium (sometimes known as ‘storksbill’), which are also in the Geraniaceae family.

… The shape of the flowers offers one way of distinguishing between the two genera Geranium and Pelargonium. Geranium flowers have five very similar petals, and are thus radially symmetrical (actinomorphic), whereas pelargonium flowers have two upper petals which are different from the three lower petals, so the flowers have a single plane of symmetry (zygomorphic).

There are, again, a huge variety of plants, many growing wild (in the fields and on the foothills around here, in particular), others cultivated. Here’s a beautiful blue cultivar, up close:


Note the veining. These are mostly modest plants, but quite attractive.

One Response to “Springing into summer”

  1. Robert Coren Says:

    I love nasturtiums, but prefer the mounding kind to the trailing kind. This year’s didn’t germinate as profusely as in some other years, and one end of the container where I always put them is kind of sparse.

    For some reason pelargoniums have never interested me (although the ones pictured above are gorgeous), but I add at least one cranesbill variety pretty much every year, although some of them don’t take.

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