Ammi is a small genus of about six species of summer-flowering plants in the carrot family Apiaceae, within the order Apiales. Native to southern Europe, northern Africa, and south-western Asia — with the type species Ammi majus hypothesised to originate from the Nile River Valley — members of this genus bear finely divided, fern-like leaves and produce broad, rounded umbels of tiny white or cream-coloured, lace-like flowers that bloom in early to mid-summer.
The most well-known species, Ammi majus (commonly called bishop's flower, false bishop's weed, laceflower, or bullwort), is a herbaceous annual or biennial that behaves as an annual in cultivation. Its lower leaves are 1–2-pinnate and upper leaves 2–3-pinnate with serrate lobes, and its compound umbel inflorescences closely resemble those of Queen Anne's lace. Ammi majus and A. visnaga, along with their cultivars, are frequently grown in gardens as ornamentals for their airy, delicate flower heads that work well in borders and cut-flower arrangements.
The genus is notable for its phytochemistry: Ammi species contain furanocoumarins including bergapten, xanthotoxin (methoxsalen), and other coumarin derivatives, along with volatile oils (camphor and carvone) and flavonol glycosides (quercetin and kaempferol). Ammi majus is considered one of the world's major natural sources of methoxsalen, a psoralen compound with potent photosensitising properties. Because of these bioactive constituents, Ammi species are prohibited under the Australian New Zealand Food Standards code.
Distribution
Ammi is native to southern Europe, northern Africa, and south-western Asia. The type species Ammi majus has a broad distribution through the Mediterranean region including Southern Europe and North Africa, extending into West and Central Asia and as far as Abyssinia; it is hypothesised to be indigenous to the Nile River Valley. The species has been introduced to the British Isles, parts of Scotland, China (where it is cultivated on medicinal farms), and is widely naturalised across temperate regions.
Cultivation
Ammi majus and A. visnaga along with their cultivars are grown in gardens as annuals or biennials, valued for their lacy white umbel flowers that resemble Queen Anne's lace. Ammi majus behaves as an annual in cultivation, blooming June–July and fruiting July–August. The plant is also cultivated commercially for its furanocoumarins, particularly xanthotoxin (methoxsalen), which is used in pharmaceutical preparations for treating skin conditions such as psoriasis and vitiligo.
Cultural Uses
Ammi majus has a remarkably long history of medicinal use. As early as 2000 BC in Egypt, the juice of the plant was applied to patches of vitiligo, after which patients were encouraged to lie in the sun — an early form of PUVA (psoralen + UVA) therapy. By the 13th century, a tincture of honey and powdered seeds of a plant called "aatrillal" was used to treat the same condition; the plant was later identified as A. majus, and the trade name Aatrillal persists today for the yellowish-brown seed powder. Modern medicine continues to use methoxsalen derived from A. majus (brand name Oxsoralen) for photochemotherapy. The plant is known in Arabic as hirz al-shayateen ('Devil's Amulet') and khella shaitani ('Devil's Toothpick-weed'), reflecting its cultural significance.
