Aquilegia (common names: granny's bonnet,[2] columbine) is a genus of about 130 species[1] of perennial plants that are found in meadows, woodlands, and at higher elevations throughout the Northern Hemisphere, known for the spurred petals[3] of their flowers.

[4] Perennial herbs, with woody, erect stock, roots forming thick rhizomes.

Five tubular honey-leaves[a] are semi erect with a flat limb and spurred or saccate at the base.

[8] Columbines are closely related to plants in the genera Actaea (baneberries) and Aconitum (wolfsbanes/monkshoods), which like Aquilegia produce cardiogenic toxins.

[12] Plants in the genus Aquilegia are a major food source for Bombus hortorum, a species of bumblebee.

Columbine is rated at hardiness zone 3 in the United States so does not require mulching or protection in the winter.

[14] The British National Collection of Aquilegias was held by Mrs Carrie Thomas at Killay near Swansea.

The plant's seeds and roots, however, are highly poisonous and contain cardiogenic toxins which cause both severe gastroenteritis and heart palpitations if consumed as food.

[11] An acute toxicity test in mice has demonstrated that ethanol extract mixed with isocytisoside, the main flavonoid compound from the leaves and stems of Aquilegia vulgaris, can be classified as non-toxic, since a dose of 3000 mg/kg did not cause mortality.

Such a "pollination syndrome", being due to flower color and orientation controlled by their genetics, ensures reproductive isolation and can be a cause of speciation.

Selection from pollinator shifts is suggested to have driven these changes in nectar spur length.