This section is from the book "Our Early Wild Flowers", by Harriet Louise Keeler. See also: Newcomb's Wildflower Guide.
Perennial. Native to Europe and escaped from gardens; common in country gardens, cemeteries, and shady places. April-November.
Trailing and creeping, rooting at the nodes; only the short flower-stems ascending.
Opposite, evergreen, shining, ovate or oblong-ovate.
Blue or white, salver-shaped, solitary in the axils of the leaves.
Tubular, five-toothed.
Blue or white, salver-shaped, border five-lobed; lobes almost wedge-shaped, convolute in bud; throat angled and thickened.
Five, inserted on the upper part or middle of the tube; filaments short; anthers bearded at the tip.
Of two carpels; style long, slender, supports a cup which is the stigma.
Two pods, each having three or four seeds; nectar-bearing.
"There sprange the violet al newe And fresh pervenke rich of hewe."
- Chaucer.
"Through primrose tufts, in that sweet bower The periwinkle trailed its wreaths; And 'tis my faith that every flower Enjoys the air it breathes."
- Wordsworth.
This is the first out-of-door flower in many country gardens where bulbs have no place; and its lovely blue flowers among the clean, glossy leaves, smiling upward to the sky, have an especial charm in the early April days. Country people know the plant chiefly as Myrtle and Periwinkle; in city parks and gardens it covers the ground as Vinca; Pliny knew it in Roman times as Per-vinca. Why the French call it Flower-of-Mystery is by no means clear, but the reason of the English name, Joy-of-the-Ground, is apparent to any one. The value of the plant lies chiefly in its hardy nature and trailing growth and the fact that it will flourish and make a green carpet under the cover of trees where little else will grow. So closely do the sterile creeping stems cling to the ground that the ancients named them serpents.
The calyx of the blossom is cut into five deep segments; the corolla forms a long tube below, expanding into a flat, five-lobed border above. The flower produces both pollen and nectar, but rarely any fruit; when it does it forms two little pods, each containing three or four seeds. The reliance of the plant for reproduction is in the long runners which develop roots at the nodes. It is now extensively used as a cover plant in parks for shaded places where nothing else will grow.

Periwinkle. Vinca minor
 
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