- Family: Buttercup Family – Ranunculaceae
- Growing form: Perennial herb.
- Height: 50–150 cm (20–60 in.). Stem glabrous or upper part sparsely hairy, blue-grey.
- Flower: Perianth zygomorphic, usually blue (there are several different-coloured cultivation varieties), 15–30 mm (0.6–1.2 in.) across. Sepals 5, petaloid, uppermost spurred, spur 12–20 mm (0.48–0.8 in.) long. Petals 4, of which 2 nectariferous, 2 vestigial, blackish–blue. Stamens 8. Gynoecium separate, pistils 2. Inflorescence branched–unbranched, quite lax raceme.
- Leaves: Alternate along stem, stalked. Blade almost as broad as long, with palmate venation, glabrous–sparsely hairy, cordate based, 3–5-lobed, lobes broad, tapered, doubly lobed–serrated.
- Fruit: 14–20 mm (0.56–0.8 in.) long follicle, of which 3 united.
- Habitat: Yards, roadsides, banks and woods near dwelling areas. Ornamental, sometimes wild.
- Flowering time: July–August.
Candle larkspur’s family’s scientific name Delphinium goes way back into history: it was used for the first time as the name of a species in the first century A.D. in a book by the Greek doctor and botanist Pedanios. Perhaps the flower’s bud was seen in some way to resemble a dolphin. The plant family has since become linked with knights in many languages. The name probably comes from the flower’s spur, which has looked like the spurs that knights used when they rode their horses to people at that time. Of the many varieties of candle larkspur that are popular as ornamentals, many took their name straight from the stories of King Arthur and the Knights of the Round Table.
Larkspurs’ distribution area includes a surprisingly large part of the northern hemisphere, and only in Africa a few species have spread to the south side of the equator. Thirty species grow in Europe, of them only candle larkspur in Finland. The natural area of its distribution begins in the Aunus region of eastern Karelia and covers European Russia and Siberia’s broad-leaf forests and damp meadows as well as central European high mountain ranges. It is very diverse and different areas of its distribution can be defined by a number of subspecies and variations. In Finland the species is generally cultivated in gardens, and it can be found especially near old countryside gardens as a leftover, especially in the north. As old native varieties are either unrefined natural forms or have been at most only slightly refined, they can survive a long time without any care or attention. The majority of candle larkspurs that are currently grown as ornamentals are hybrids, and their descendants are the product of cultivation. They belong to the perennial elite, but they are too demanding with regards to habitat and care to survive in the Finnish wilds. All Delphinium species (worldwide about 300 is known) are considered toxic to humans. So are also monkshood (Aconitum napellus) and nothern wolfsbane (A. lycoctonum) which can be mixed with candle larkspur when not flowering.