Viola Fact Sheet

Introduction

Violas are now competing with their pansy cousins as superstars of the cool season garden. Always easy to grow, newer viola varieties offer larger flower size, along with excellent heat resistance and cold tolerance, for exceptional garden performance. The flower color palette is unsurpassed, offering beautiful pastels and sparkling jewel tones. Some flowers have two, even three colors. Many have unique patterns and markings. The fresh green foliage provides a canvas that makes the abundant flowers shine.

Violas have gained popularity with gardeners in all regions of the country. In northern climates, violas grace the garden during the spring and early summer, often flowering into the fall. Newer viola hybrids are exceptionally cold hardy and may even survive northern winters with proper care and plenty of mulch. In the South, violas are essential in the fall garden, providing continuous bloom through winter and spring, lasting until summer’s heat takes its toll. Their popularity will continue to grow as new varieties of violas, with even better garden performance, become available.

History

Violas have been celebrated throughout history, not only in gardening, but also in literature, medicine, and art. Most of the historical references probably refer to the Sweet Violet (Viola odorata), one of the first flowers to be grown commercially. Violas came from Europe, where they grew wild throughout the region, and were familiar as early as the 4th century BC to people living in Greece, who cultivated the plants for herbal medicinal use.

Reference to the modern day viola can be found dating back to 1633. Gerard’s The Herbal describes the Heartsease (V. tricolor) as having “forme and figure like the Violet, and for the most part of the same bigness, of three sundry colours, … that is to say, purple, yellow, and white or blew.”

Heartsease has been used for centuries as an herbal treatment for a wide range of ailments including epilepsy, asthma, eczema, and other skin diseases. It was also used to treat respiratory problems such as bronchitis and whooping cough, as well as rheumatism. The flowers, leaves, and roots of Viola are still used by many herbalists today.

V. tricolor is known by hundreds of common names including Love in Idleness, Call Me to You and Three Faces in a Hood. It was also called the Trinity herb because of the three-colored flowers. When brought to North America in the 18th century, the plant became known as Johnny-jump-up. It was grown by Thomas Jefferson who noted that he planted it at his birthplace, Shadwell, on April 1, 1767.

Nomenclature

Viola is a large genus of about 500 species that includes many popular wildflowers and garden flowers such as pansies, sweet violets, and Johnny-jump-ups. They represent a wide range of growth habits and include annuals, biennials, and deciduous perennials. Most garden violas are grown as annuals or short-lived perennials.

The ancestor of today’s violas is the Sweet Violet, V. odorata. A true perennial, Sweet Violet is known for its compact plant growth and small, sweetly fragrant, deep violet flowers.

Garden violas are represented by two species. One species is Viola tricolor, Johnny-jump-up. This perennial is native to Europe and Asia, grows about 6-10 inches high, and produces small, nickel-sized flowers in purple, yellow, and white with interesting marks or whiskers. Johnny-jump-ups are often grown as an annual.

The other is Viola cornuta, sometimes called tufted pansies or horned violets. Native to Spain and the Pyrenees, V. cornuta grows throughout temperate regions of the world. The green leaves form spreading, perennial, evergreen rosettes. Plants are compact, up to 8-10 inches tall, with 1 1/2-inch diameter flowers patterned with rays or lines in a deeper or contrasting color. Flowers may have a light scent.

Closely related is the garden pansy, Viola wittrockiana, this short-lived perennial has larger flowers than V. tricolor or V. cornuta. Pansies reach a height of about 8 inches tall with single colored or face patterned flowers that measure 2-3 inches across, though some hybrids have even larger flowers. Pansies are generally grown as annuals.

Classification

Violas can be grouped in several different ways. Plants may have a compact, mounded growth habit or a spreading, trailing habit. Flowers can be small - under 1-inch in diameter, or large - over 1-inch. Varieties are open-pollinated or hybrid. While classifying violas may be confusing, their usefulness and beauty in the garden are clear.

‘Helen Mount’ is a popular Johnny-jump-up (Viola tricolor). This open-pollinated variety has small, 3/4-inch diameter flowers in purple, lavender, and yellow. It is readily available in seed packets from retail stores and mail order catalogs, as well as bedding plants from nurseries and garden centers. ‘Helen Mount’ easily reseeds, producing plants similar to the parent plants.

Classic, older varieties of Viola cornuta include ‘Arkwright Ruby’ with dark wine red flowers and golden centers and edging. ‘Chantreyland’ is popular for its large apricot-colored flowers. ‘Yellow Perfection,’ ‘White Perfection’ and ‘Blue Perfection’ are named for the clear color of their blooms. These varieties are all open-pollinated.

Newer open-pollinated varieties of V. cornuta  are the ‘Princess’ and ‘Velour’ series. These are early blooming with 1-inch blooms. ‘Princess’ opens in shades of blue, purple and yellow and bicolors; and ‘Velour’ is available in 20 colors and 3 mixes.

Many excellent hybrid violas are available mainly as bedding plants. Hybrid varieties offer exceptional garden performance, good flower production, and uniform growth. ‘Sorbet™’ violas come in more than thirty colors including beautiful pastel and two-tone colors on compact plants reaching 6-8 inches tall. ‘Penny™’ violas are available in shades of light blue, deep blue, purple, violet, white, yellow, orange and red. Some have whiskers and blotches (faces) others are bicolor. They have a mounding garden habit and flower continuously.

In 2006, ‘Skippy™ XL Red-Gold,’ a hybrid Viola cornuta, was the first viola to win an All-America Selections award for superior garden performance. The large, 1 1/2-inch flowers are ruby red with violet-red shading below a golden yellow face with the trademark whiskers or markings. The ‘Skippy™’ series has many other colors, including bicolors.

One of the largest flowered violas is the hybrid ‘Patiola®’ series, combining the flower size of pansy with the hardiness of violas. Flowers grow to 2 inches in diameter and bloom in yellow, blue, orange and violet. The newest color in the series is brick red with a golden yellow center.

Trailing violas have a low growing, spreading habit that is perfect for hanging baskets, containers or use as a groundcover. There are several hybrid varieties available. ‘Erlyn’ produces tricolor purple and yellow flowers that cover the plant. The ‘Splendid’ series has 1-inch flowers in white, yellow, and blue and yellow. Plants spread up to one foot in diameter.

How to Grow

There are two different times for planting violas depending on your climate. In cold winter areas, plant violas outdoors in early spring. In regions with warm or mild winters, violas are planted in fall after summer’s heat is over.

Starting from Seed Indoors

Viola seed should be started indoors about 4 to 6 weeks before transplanting outdoors. Northern gardeners should start seeds in January and February. In the South, start seeds in July and August for fall flowering plants.

Thoroughly moisten sterile seed-starting mix, and then fill your flats, trays, or pots to within 1/4-inch of the top of the container. Put 2-3 seeds in each cell or small pot, and then cover with moist soil almost to the top. Seeds need darkness to germinate so make sure they are completely covered. Place in a warm location until seeds begin to grow about 10-14 days later. A room temperature of 65º-70ºF is ideal for starting seeds. After seedlings appear, move the container to a bright, sunny window or place under plant lights.

When seedlings have a couple sets of leaves, thin to the strongest plant by pinching or cutting excess seedlings at the soil line. Seedlings should be grown in slightly cooler temperatures of 55º-60ºF. Many seed starting mixes include slow-release fertilizer for healthy plants. If your mix does not contain fertilizer, begin applying a water-soluble fertilizer according to label directions about two weeks after seedlings appear.

Before transplanting the tender seedlings into the garden they need to be hardened off, allowing them to adjust to the outdoor conditions. Place seedlings outdoors in a shaded or protected location for short periods of time, about 4 hours per day to start. Each day, leave plants outdoors for a couple hours longer and gradually move into brighter light conditions. Check the soil often to make sure it’s moist, and water if necessary. After 10-14 days, violas can be planted in the garden even if light frost is still possible.

Direct-seeding into the Garden

While starting seeds indoors is recommended, violas can be started directly in the garden where they are to grow. Good soil preparation is the key to success. Violas prefer a moist but well drained, fertile soil. Prepare the area by digging the soil to a depth of about 6 inches, making sure to remove rocks and break up clumps of soil. Add an inch of compost or composted manure and work into the existing soil. Scatter seeds then cover with 1/4-inch of fine soil. Water regularly so the seedbed stays moist. As seedlings grow, thin to 6-8 inches apart. Excess seedlings can be transplanted, when small, to other areas in the garden or planted in containers.

Purchasing Bedding Plants

Most violas will be sold with flower buds, or in bloom, in 4- or 6-plant packs. Select healthy, compact plants with green leaves. Avoid plants that show signs of yellowing which may indicate a problem with the roots or a nutrition problem. Plants that are stressed in the container may take more time to become established in the garden, often develop poorly, and never flower well. Also avoid plants that have a lot of roots growing through the bottom of a plastic container. They will be hard to remove without doing damage to the root system.

To remove plants from the pack, push up on the bottom of the container; don’t pull plants by the stem. Gently loosen the soil around the roots and place in the ground so that the plant is at the same level as in the pack.

Planting in the Garden

• Soil: Violas grow best in rich, moist, well-drained soil with plenty of organic matter. Mix a slow-release fertilizer into the soil at planting time or occasionally fertilize with a balanced fertilizer. Water when the soil is dry to maintain even moisture.

• Sunlight: It is important for violas to receive enough sun yet be protected from extreme heat. In warm climates, violas do best when they are shaded during the hottest part of the day. Morning sun and afternoon shade are ideal. Mulch helps keep the soil cool and moist. Violas grow in a wide range of temperatures from 30º-80ºF. They will even survive overnight temperatures in the upper teens if it warms up during the day. Plants flower sparsely and eventually die when temperatures stay above 90ºF for extended periods of time.

• Spacing: Plant mounded violas about 6-8 inches apart. Trailing or spreading varieties can be planted 10-12 inches apart.

• Days to Bloom: Violas begin blooming about 12-14 weeks after planting seeds. V. tricolor varieties bloom about two weeks earlier than V. cornuta. ‘Penny’ and ‘Sorbet’ will bloom 9-10 weeks from sowing.

• Plant Care: To promote blooming and extend the flowering period, remove or deadhead faded flowers by pinching off the blooms at the base of the flower stem. Revive leggy or overgrown plants by cutting them back to about 3-4 inches tall. Violas often self-seed, though newer hybrid varieties will not produce plants that look like the ones you planted.

• Insects and Diseases: Violas are easy to grow, with few disease or insect problems. Avoid diseases such as powdery mildew or botrytis by planting violas in an area that receives plenty of light and good air circulation. Aphids can be washed off with a strong stream of water, or, for severe problems, treat with an insecticidal soap.

Garden Uses

Viola’s size, compact habit, and long flowering period are perfect for containers, hanging baskets and garden beds. Mounded plants make a lovely edging along a path or to define a garden border. Trailing varieties are exquisite in hanging baskets, filling crevices in rock walls and tumbling over the edge of containers and window boxes.

Violas can be mixed with other garden flowers for stunning combinations in garden beds or containers. They make a wonderful choice for planting with other cool-loving garden flowers such as snapdragons, calendula, and dianthus. Or tuck violas between spring flowering bulbs such as tulips and daffodils to fill the space as the bulbs fade.

Versatile Violas

Viola flowers are beautiful in the garden and on the table. Not just for fresh bouquets, violas are very popular edible flowers. Culinary uses include jams and jellies, teas, garnishes and salads. Candied violas are easy to make and look stunning atop cakes, ice cream, cookies, or other desserts.

In addition, viola flowers make wonderful dried or pressed flowers and their smaller size is ideal for a variety of craft uses.

For More Information

Please consider our NGB member companies as authoritative sources for information. Click on direct links to their websites by selecting Member Info from the upper left menu on this page, and then click on Complete Member List located at the bottom of the page. Gardeners looking for seed sources, select companies listed as Retail.

 

The National Garden Bureau recognizes Janis Kieft as the author of this fact sheet. We wish to thank the Viola experts who reviewed our text. Jason Jandrew of Goldsmith Seeds, Inc. and Jaggi Sharma of PanAmerican Seed greatly assisted our efforts to provide accurate information.

 

This viola fact sheet is provided as a service from the National Garden Bureau. The use of this information is unrestricted. Please credit the National Garden Bureau as the source.