Violet Reaction

by | Feb 1, 2009 | Native Plants

EACH SPRING, LONG BEFORE OTHER flowers appear from beneath the ground, violets (Viola spp.) light up the landscape with their perky, colorful blossoms. Predecessor to the prolific pansy, violets bloom with abandon just about anywhere and are generally easy to grow. And while they may not make headlines like flashier flowers, they do have a devoted following. Illinois, New Jersey, Rhode Island and Wisconsin all honor the violet as their state flower.

For many violet lovers, the fascination with these lovely wildflowers dates back to childhood, says American Violet Society member Thomas Silvers, who grows native violets in his Frederick, Maryland, garden. “As a child, I remember being entertained by all of the tiny flowers growing in my lawn,” he remembers.

Plant biologist Theresa Culley was in graduate school when she saw native violets for the first time, in 1994. “A naturalist friend told me how violets make blooming and non-blooming flowers, so I went out into the woods near Ohio State to see for myself and found the yellow Viola pubescens. I ended up studying that violet and Viola canadensis for my graduate work,” says Culley, who is now an associate professor in the Department of Biological Sciences at the University of Cincinnati. She says she is still intrigued by their intricate beauty and demure blossoms.

The genus Viola encompasses approximately 60 North American native species and as many as 400 worldwide. These mostly herbaceous perennials can grow from sea level to over 10,000 feet elevation, according to Dr. John Little, president of Sycamore Environmental Consultants Inc. in Sacramento, California, who is also senior author with Landon McKinney of the genus Viola for the upcoming “Flora of North America” (2008). “Native Viola species occur in numerous types of habitats, such as wet meadows, along streams, around lakes, in forests, plains, bogs, grasslands and deserts,” he says.

Although violets are often considered to inhabit only temperate climates, there are also species in tropical locales such as Hawaii, says Harvey Eugene Ballard, Jr., associate professor of plant systematics and evolution in the Department of Environmental & Plant Biology at Ohio University. As its name suggests, kauaensis is found on the island of Kauai. It is a stemmed species with rounded smooth leaves and white and purple fragrant flowers. Violets make good cut flowers, lasting in water for several days, and their blooms come in a variety of colors including deep blue, purple, white and yellow. Some flowers are even speckled or spotted. Certain species, such as V. odorata, have a distinct, memorable fragrance and as a result have been used in the perfume industry.

Violets generally have five petals, and some people eat the leaves and flowers, says Rebecca Peters of the California Academy of Sciences in San Francisco. “We also have violets to thank for the garden pansies we enjoy today,” she says, adding that these introductions were developed from hybrids of the Eurasian native V. tricolor and other species.

Native violets also do the important job of supplying food for insect pollinators such as bees, flies and butterflies, particularly butterfly larva. “Violets are the required food for some fritillary larva,” says Gary W. Sherwin, president and webmaster for the American Violet Society, which is based in Yukon, Pennsylvania. “Violet leaves and flowers are also food for deer, rabbits and other herbivores, and the seeds are a food source for ants.”

The violet has a long, colorful history. “Shakespeare and other authors and poets referenced violets in their writing,” says Sherwin, who has training as a biologist with an emphasis on taxonomy. “Many people are also unaware that they were the first commercially grown flowers in the U.S. and for many years were sold extensively in this country. Somewhere between the two world wars, however, U.S. nurserygrown violets were hit by disease and their popularity waned. Later, Eleanor Roosevelt caused a revival in the violet-growing industry, and there are still a few growers today.” The First Lady wore violets at her husband’s presidential inaugurations and was known to bestow the flowers on visiting royalty. Throughout the Roosevelt administrations, violets were delivered weekly to the White House.

For the purposes of classification, violets come in stemless (acaulescent) and stemmed (caulescent) species. With a stemless violet, the peduncle (flower stem) comes directly off a rhizome in the soil. Viola rotundifolia is an example of this, and V. canadensis is a stemmed species. Some species also have a spur at the back of the flower, which is often unnoticeable except in the case of V. rostrata, which has a large, eye-catching spur that has become that species’ trademark.

Another unusual aspect of violets is the fact that each plant produces two entirely different types of flowers. There are the showy (chasmogamous) flowers we all think of as violets and then there are self-pollinated (cleistogamous) flowers, which do not open or have petals. Culley and other researchers have come to the conclusion that the reason for the two flower types has to do with changing light levels throughout the year.

“In early spring in the forest there are high light levels and no forest overstory, so the angle of the sun, longer day length and warming of the soil triggers violets to start growing,” says Culley. “At this point, insect pollinators are busy flying around, and it’s easier for them to see the showy flowers. The minute the forest canopy starts to fill in, however, the flowers stop appearing and buds are even aborted. The plants then start producing the second type of flower that doesn’t need pollination. This flower looks like a bud but becomes a seed capsule without ever blooming.”

As their dual methods of propagating show, when it comes to establishing themselves in the landscape, violets are anything but shrinking in their behavior. They actually have a reputation as being somewhat aggressive. “Violets are sometimes called weeds, but I just laugh,” says Anne Belle Rice of Long Beach, California. Rice is vice president of the original International Violet Society and has served as president of the American Violet Society. “I tell people they are wonderful weeds, and we should all be lucky to have them in our landscape.”

The violet’s seed dispersal method is partially responsible for its sometimes fast-spreading reputation. “Most violet species have ballistic seed dispersal, meaning that seeds can be dispersed up to 5 meters away from the mother plant,” says Culley. “As the seed capsule dries, the seeds are pinched and then they fling out.”

Many stemless violets also produce stolons (runners), which enable genetically identical plants (clones) to develop nearby. Some, like V. sororia, can be fairly aggressive, while others are more restrained. “I have a lot of [the stemless] Viola labradorica in my garden,” says Culley, who notes that for her this is a tidy species that doesn’t spread much but grows in a clump that gets slightly larger every year.

Keeping violets from multiplying more rapidly than you’d like can be accomplished however you prefer – either by pinching off fruits before they release seed or by removing established plants later on.

In order to have luck growing violets, it’s important to choose the right violet species for your climate and your situation, says Culley. “Some species are nearly impossible to grow, while others are no problem at all,” she says. “Like orchids, violets can be very choosy about their growing conditions.”

When it comes to selecting violets that will grow well for you, Sherwin suggests taking a look at your grass and encourage the ones already growing there. “In every square foot of my yard you’ll find about 15 different plant species. I gradually raised my mower to the top setting to provide a groomed, but still diverse ecosystem with better health and less maintenance, energy and required water. A side effect is that the violets and other flowering species have a chance to bloom.”

Most violets prefer well-drained moist soil and partial shade. Removing competing weeds is also important, says Barry Glick, owner of Sunshine Farm & Gardens in Renick, West Virginia, which carries a variety of native violas.

It is possible to grow some violets in containers, and Sherwin has had success using a sandy soil mix that includes a limestone base when doing so. Good varieties for container culture include lobed violet (V. lobata), bird’s-foot violet (V. pedata), sagebrush violet (V. trinervata) and Shelton’s violet (V. sheltonii).

Whether you grow your violets in the ground or containers, be prepared for their delicate beauty to enchant you. And don’t be surprised if you find yourself tucking as many as you can into your garden. “The more violets in my yard, the better,” says Sherwin, who notes that the number-one request the American Violet Society receives is how to get violets out of the yard. “I just laugh and answer that they’re asking the wrong person,” says Sherwin. “I plant them in my yard, and I plant plenty.”