Diggin’ In: Witch hazel can make a winter garden bloom

October 12, 2015

Too often, too much gardening is all about spring and summer.

Late-fall and winter-flowering plants like witch hazel change all that, according to native plant expert Helen Hamilton, a Williamsburg Virginia resident who taught biology, chemistry and earth science for 30 years. She is past president of the John Clayton Chapter, Virginia Native Plant Society, and co-author of "Wildflowers and Grasses of Virginia’s Coastal Plain."

"Crinkly, yellow, strap-shaped flowers cover native witch hazel October through December," she says.

"Cultivars are available that bloom in deep winter, under snow and ice in January, with reddish-gold ribbons of flowers."

The plant, scientifically known as Hamamelis virginiana, requires insect pollination, and biologists have been puzzled about how a pollinating insect could be flying in cold weather. In a 1987 article in Scientific American magazine, Bernd Heinrich describes how some species of owlet moth are active in winter, Hamilton noted. When temperatures are below freezing, they rest and hide under leaves for insulation and protection. They find food at night and raise their body temperature by shivering to warm up. They generally feed on the sap of injured trees, but are known to take nectar from the blossoms of witch hazel, which fertilizes the flowers.

In summer, witch hazel branches are covered with lustrous dark green leaves, slightly pointed with somewhat wavy edges. The small, pointed growths often seen on some of the leaves are the homes of the witch hazel cone gall aphid, which is harmless to the plant, according to Hamilton.

For a later-flowering witch hazel, there’s Hamamelis x intermedia, a hybrid of two Asian species — H. japonica and H. mollis. Blooming January through March, it has bronze to deep-red flowers, depending upon the cultivar; the leaves turn yellow, orange and red in fall. Also, there’s the Chinese witch hazel (H. mollis), noted for its larger yellow flowers and stronger fragrance, according to Hamilton.

Two other witch hazel species native to North America — Ozark witch hazel (H. vernalis) and Leonard’s Witch Hazel (H. ovalis) — occur only in a few southeastern states. The nursery trade uses these species to form hybrids, according to Hamilton

The origin of "witch" in this plant’s name is a mystery, but it may have come from Middle English wiche, meaning "plant" or "bendable," Hamilton adds. Some believed a tea made from the leaves or bark had magical powers. Native Americans thought there was something very strange about a plant blooming in the dead of winter.

Witch hazel has long been used as a nonprescription drug to relive itching, hemorrhoids and minor pains.

All about aphids

Aphids, nicknamed plant lice, are small, soft-bodied insects, according to Hamilton. There are hundreds of different species of aphids, some of which attack only one host plant while others attack numerous hosts. Most aphids are green and black, but their bodies can be gray, brown, pink, red, yellow or lavender. A characteristic common to all is the presence of two tubes, called cornicles, on the back ends of their bodies. Some species, known as wooly aphids, are covered with white, waxy filaments.

Aphids feed in clusters and generally prefer new succulent shoots or young leaves. The tiny insects feed by sucking up plant juices through a food channel in their beaks. At the same time, they inject saliva into the host and may transmit plant diseases as they feed, she adds. Light infestations usually do not harm plants, but bad infestations can cause leaf curl, wilting, stunted shoot growth, slower fruit and flower production and general plant decline.

Aphids also cause a sticky honeydew substance to collect on lower leaves, which can be covered by fungi known as sooty molds. These crusty molds interrupt the food-making photosynthesis process in leaves.

When plants are growing vigorously, check them twice a week to catch infestations early, which is a good time to remove them with a blast of cold water or to prune them out, Hamilton suggests. Many aphids cause the worst damage in late spring before temperatures rise.