The Nasturtium

THE NASTURTIUM

Teacher’s Story

“Little warriors, brave and fearless, with shields of emerald green,
Are climbing over fence rails, and everywhere are seen
Looking down on every side, while her brave Nasturtium army,
Queen Nature views with pride.”

—Ray Laurence.

It is quite fitting that the nasturtium leaves should be shaped like shields, for that is one of their uses; they are shields to protect the young nasturtium seeds from the hot sun and from the view of devouring enemies. The nasturtiums are natives of Peru and Chili, and it is fitting that the leaves should develop in shield-shape, and the shields overlap until they form a tent to shade the tender developing fruit from the burning sun. But they were never meant to shield the flower, which thrusts its brilliant petals out between the shields, and calls loudly to the world to admire it. It would indeed be a pity for such a remarkable flower to remain hidden; its five sepals are united at their base, and the posterior one is extended into a long spur, a tube with a delectable nectar-well at its tip. The five petals are set around the mouth of this tube, the two upper ones differing in appearance and office from those below; these two stand up like a pair of fans, and on them are lines which converge; on the upper sepals are similar lines pointing toward the same interesting spot. And what do all these lines lead to, except a veritable treasure-cave filled with nectar! The lower petals tell another story; they stand out, making a platform, or doorstep, on which the visiting bee alights. But it requires a big insect to do the work of this flower, and what if some inefficient little bee or fly should alight on the petal-doorstep and steal into the cave surreptitiously! This contingency is guarded against thus: Each of these lower petals narrows to a mere insect footbridge at their inner end; and in order to render this footbridge quite impassable, it is beset with irregular little spikes and projecting fringes, sufficient to perplex or discourage any small insect from crawling that way.

But why all these guiding lines and guarded bridges? If you watch the same blossom for several successive days, it will reveal this secret. When a flower first opens, the stamens are all bent downward, but when an anther is ready to open its pollen doors, the filament lifts it up and places it like a sentinel blocking the doorway to the nectar treasure. Then when the robber comes, whether it be butterfly, bee or hummingbird, it gets a round of pollen ammunition for its daring. Perhaps there may be two or three anthers standing guard at the same time, but, as soon as their pollen is exhausted, they shrivel and give room for fresh anthers. Meanwhile, the stigma has its three lobes closed and lying idly behind and below the anthers; after all the pollen is shed, the style raises and takes its position at the cave entrance and opens up its stigmas, like a three-tined fork, to rake the pollen from any visiting insect, thus robbing the robber of precious gold-dust which shall fertilize the seeds in its three-lobed ovary. Although the flower needs to flare its colors wide to call the bees and hummingbirds, yet the growing seeds must be protected; therefore, the stem which held the flower up straight, now twists around in a spiral and draws the triplet seeds down behind the green shields.

Nasturtium leaves are very pretty, and are often used as subjects for decorative water-color drawings. The almost circular leaf has its stem attached below and a little at one side of the center; the leaves are brilliant green above but quite pale beneath, and are silvery when placed beneath the water. The succulent stems have a way of twisting half around the wires of the trellis and thus holding the plant secure to its support. But if there is no trellis, the main stem seems to awaken to the responsibility and grows quite stocky, often lifting the plant a foot or two in height, and from its summit sending out a fountain of leaf and flower stems.

The nasturtium is among the most interesting and beautiful of our garden flowers, and will thrive in any warm, sunny, fairly moist place. Its combinations of color are exceedingly rich and brilliant. H. H. says of it:

“How carelessly it wears the velvet of the same
Unfathomed red, which ceased when Titian ceased
To paint it in the robes of doge and priest.”