- October 19, 2016 - Jardin botanique : Secrets of plants
In October, common or American witch-hazel (Hamamelis virginiana), a shrub native to southern Quebec, is covered in delicate yellow flowers that really come into their own once the leaves drop off.
A perfect name for Halloween
The species common name of witch-hazel is particularly fitting for Halloween. While the name’s origin is uncertain, the “witch” part of it may come from the Old English word wice or wyche, meaning “pliant” or “bendable,” referring to the plant’s twigs. It may also suggest a link with medicinal use. The fact that the twigs were once used as divining rods, as were hazelnut twigs, may have influenced the “witch” part of the name, as well.
A late, magical fall show
Whereas some witch-hazel species, like Hamamelis mollis, H. vernalis and H. x intermedia, bloom in early spring or even late winter, American witch-hazel (H. virginiana) flowers in late autumn. In fact, it is one of the last woodland shrubs to bloom.
The small yellow, fragrant and wispy flowers have four narrow, twisted, strap-like petals that some people say resemble small golden spiders. They appear when the leaves turn yellow in autumn, and often go unnoticed, hidden amongst the foliage. Surprisingly, they remain on the twigs for several weeks, putting on a spectacular show after the leaves are gone.
The flowers are frost hardy and well adapted to cool autumn temperatures. The petals curl up when the mercury drops and then unfurl again as temperatures rise, allowing insects to pollinate them. The small amounts of nectar secreted by the staminodes (sterile stamens) are what attract pollinating insects, which cross-pollinate the flowers on warm days. Unfortunately, there may not be many insects around at this time of year, even though these flowers are one of the few pollen sources available.
Because pollination occurs late in the season, the pollen and ovules remain dormant over the winter and fertilization takes place the next spring. As a result the seeds don’t mature until the next fall, and are dispersed late in the season when the plant blooms. Once the capsule containing the seeds becomes dry, it contracts until it explodes with a characteristic cracking sound, ejecting the seeds up to 5 or even 10 metres away from the shrub! It is the only North American shrub whose twigs can bear the next season’s buds, flowers and ripe fruit all at the same time.
At the Jardin botanique, you can see American witch-hazels in various gardens, including the Medicinal Plant Garden, the Shrub Garden and the Japanese Garden.
