Viola tricolor is a small plant of creeping and ramping[a] habit, reaching at most 15 centimetres (6 in) in height, with flowers about 1.5 cm (1⁄2 in) in diameter.

In Iceland, Viola tricolor is known to be a host for at least two species of plant pathogenic fungi, Pleospora herbarum and Ramularia agrestis.

As some of its names imply, V. tricolor and other plants in the Viola genus (such as V. odorata, or sweet violet), have a long history of use in herbalism and folk medicine, particularly Iranian, Greco-Arab, Ayurvedic and Unani traditional health systems.

Studies have shown V. tricolor extract has antinociceptive,[7] immunosuppressant[8] and anti-inflammatory[9] properties, making it a potential treatment for autoimmune disorders.

[17] Some studies have discovered potential anti-cancer properties, where the extract (primarily the ethyl acetate component) has been attributed to induced apoptosis and inhibited angiogenesis in cancer cells.

[citation needed] The flowers have also been used to make yellow, green and blue-green dyes,[22] while the leaves can be used to indicate acidity.

[24] V tricolor leaves, stems, roots and flowers have been found to contain antioxidants and flavonoids (including violanthin, violaquercitrin, quercetin, luteolin, and rutin),[25][24][26][27][7] amino acids,[28][21] chlorogenic acids,[7] salicylates,[7][19] as well as alkaloids, volatile oils, mucilage gums, resin, saponins, and vitamins A and C.[6][29][9][5] Various carotenoids have also been isolated from the drug, including violaxanthin, antheraxanthin, lutein, zeaxanthin and beta-Carotene.

[30] The fresh plant Viola declinata and V. tricolor contains approximately: Its 10 percent mucilages consist of glucose, galactose, arabinose and rhamnose, as well as tannins, salicylic acid, and its derivatives.

[31] Heartsease contains compounds, including colorless crystalline compounds,[clarification needed][32] proven to be useful in prophylaxis and treatment of some medical conditions (see Traditional and Medicinal Uses section), such as cardiovascular problems, complications of diabetes, inflammations,[9][7] immune disorders, and liver problems, among other indications.

These small peptides have proven to be useful in drug development due to their size and structure giving rise to[clarification needed] high stability.

[34][33][19][18][20] According to Roman mythology, the wild pansy turned into the Love-in-idleness as Cupid shot one of his arrows at the imperial votaress, but missed and instead struck it.

According to Greek mythology, Zeus fell in love with a young woman named Io and provoked jealousy to his wife Hera.

For pity on the diet of herbs to which he submitted the beloved, he caused the earth to produce beautiful flowers that he called Io.

Oberon's account is that he diverted an arrow from Cupid's bow aimed at "a fair vestal, throned by the west" (supposedly Queen Elizabeth I) to fall upon the plant "before milk-white, now purple with love's wound".

The juice of the heartsease now, claims Oberon, "on sleeping eyelids laid, Will make or man or woman madly dote Upon the next live creature that it sees."

A Midsummer Night's Dream (Act 2, Scene 1) The love-in-idleness was originally a white flower, struck by one of Cupid's arrows, which turned it purple and gave it its magic love potion.

In the end, the love-in-idleness nectar is used to restore all romances in the play to their original states (including Demetrius's prior affections for Helena before he turned to Hermia.)

till I found it to be true, I never thought it possible or likely; But see, while idly I stood looking on, I found the effect of love in idleness; And now in plainness do confess to thee, That art to me as secret and as dear As Anna to the Queen of Carthage was, Tranio, I burn, I pine, I perish, Tranio, If I achieve not this young modest girl.

In her poem Balm in Gilead, Christina Georgina Rossetti uses heartsease as a metaphor of growing older as her confidence and her vision increases.