Pansy

Pansy
Scientific classification
Kingdom:	Plantae
Unranked:	Angiosperms
Unranked:	Eudicots
Unranked:	Rosids
Order:	Malpighiales
Family:	Violaceae
Genus:	Viola
Species:	V. tricolor
Subspecies:	V. t. subsp. hortensis
Trinomial name
Viola tricolor subsp. hortensis

The pansy or pansy violets are a large group of hybrid plants cultivated as garden flowers. Pansies are derived from Viola species Viola tricolor hybridized with other viola species, these hybrids are referred to as Viola × wittrockiana or less commonly Viola tricolor hortensis. The name "pansy" also appears as part of the common name for other Viola species that are wildflowers in Europe. Some unrelated species, such as the Pansy Monkeyflower, also have "pansy" in their name.

Cultivation, breeding and life cycle

Pansy breeding has produced a wide range of flower colors including yellow, gold, orange, purple, violet, red, white, and even black (very dark purple) many with large showy face markings. A large number of bicoloured flowers have also been produced. They are generally very cold hardy plants surviving freezing even during their blooming period. Plants grow well in sunny or partially sunny positions in well draining soils. Pansies are developed from viola species that are normally biennials with a two-year life cycle. The first year plant produce greenery and then bear flowers and seeds their second year of growth and afterwards die like annuals. Because of selective human breeding, most garden pansies bloom the first year, some in as little as nine weeks after sowing.

&nbsp Most biennials, including pansies, are purchased as packs of young plants from garden centres and planted directly into the garden soil. Under favourable conditions, pansies can often be grown as short lived perennial plants, but are generally treated as annuals or biennial plants because after a few years of growth, the stems become long and scraggly. Plants grow up to nine inches (23 cm) tall, and the flowers are two to three inches (about 6 cm) in diameter, though there are some smaller and larger flowering cultivars available also.

Pansies are winter hardy in zones 4-8. They can survive light freezes and short periods of snow cover, in areas with prolonged snow cover they survive best with a covering of a dry winter mulch. In warmer climates, zones 9-11, pansies can bloom over the winter, and are often planted in the fall. In these climates, pansies have been known to reseed themselves and come back the next year. Pansies are not very heat-tolerant; they are best used as a cool season planting, warm temperatures inhibit blooming and hot muggy air causes rot and death. In colder zones, pansies may not persist without snow cover or protection (mulch) from extreme cold or periods of freezing and thawing.

Pansies, for best growth, are watered thoroughly about once a week, depending on climate and rainfall. The plant should never be overwatered. To maximize blooming, plant foods are used about every other week, depending on the type of food used. Regular deadheading can extend the blooming period.

Morphology

The pansy flower has two top petals going over each other slightly, two side petals, connectors where the three lower petals join the center of the flower, and a single bottom petal with a slight marking. The pansy plant can come in a variety of different and vibrant colors that are pleasing to the eye.

Diseases

Stem rot

Stem rot, also known as pansy sickness, is a soil-borne fungus and a possible hazard with unsterilized animal manure. The plant may collapse without warning in the middle of the season. The foliage will flag and lose color. Flowers will fade and shrivel prematurely. Stem will snap at the soil line if tugged slightly. The plant is probably a total loss unless tufted. The treatment of stem rot includes the use of fungicides such as Cheshunt or Benomyl, which are used prior to planting. Infected plants are destroyed (burned) to prevent the spread of the pathogen to other plants.

Leaf spot

Leaf spot (Ramularia deflectens) is a fungal infection. Symptoms include dark spots on leaf margins followed by a white web covering the leaves. It is associated with cool damp springs.

Mildew

Mildew (Oidium) is a fungal infection. Symptoms include violet-gray powder on fringes and underside of leaves. It is caused by stagnant air and can be limited but not necessarily eliminated by spraying (especially leaf undersides).

Tower cucumber menace virus

The cucumber mosaic virus is transmitted by aphids. Pansies with the virus have fine yellow veining on young leaves, stunted growth and anomalous flowers. The virus can lay dormant, affect the entire plant and be passed to next generations and to other species. Prevention is key: purchases should consist entirely of healthy plants, and pH-balanced soil should be used which is neither too damp nor too dry. The soil should have balanced amounts of nitrogen, phosphate and potash. Other diseases which may weaken the plant should be eliminated.

Pests

Slugs and snails

Slugs and snails feed on the foliage. Sometimes sharp, gritty sand or a top-dressing of chipped bark is used by gardeners to limit damage.

Aphids

Aphids, which can spread the cucumber mosaic virus, sometimes feed on pansies. Infestations are treated with a spray of diluted soft soap (2 ounces per gallon) or insecticides.

Cultivars

The Universal Plus series of 21 cultivars covers all the common pansy colours except orange and black.