Allium ursinum umbel of six to 20 white flowers only, lacking the bulbils produced by some other "Allium" species such as "Allium vineale" (crow garlic) and "Allium oleraceum" (field garlic). It flowers in the British Isles from April to June, starting before deciduous trees leaf in the spring. The flower stem is triangular in cross-section and the leaves are broadly lanceolate similar to those of the lily of the valley ("Convallaria majalis"). It is native to temperate regions of Europe, from Britain east to the Caucasus. It is common in much of the lowland British Isles with the exception of the far
Basics of white flower colouration Basics of white flower colouration White flower colour is related to the absence or reduction of the anthocyanidin content. Unlike other colors, white colour is not induced by pigments. Several white plant tissues are principally equipped with the complete machinery for anthocyanin biosynthesis including the expression of regulatory genes. Nevertheless, they are unable to accumulate red or blue pigments, for example Dahlia ´Seattle´ petals showing a white tip. Several studies have revealed a further reduction of the anthocyanidin to colorless epicatechin by the enzyme anthocyanidin reductase (ANR). Many external factors can influence colour: light, temperature, pH, sugars and metals. There