Celery

Celery (Apium graveolens L.) is a biennial herb — sometimes a perennial that flowers only once and then dies — about 30–100 cm tall when grown as a vegetable and up to 1–1.5 m when it sends up its flowering stem. The whole plant has the characteristic celery odour. The stem is erect, smooth, solid, with conspicuous longitudinal grooves and branches near the top. The leaves are bright green, 1- to 2-pinnate, with long stalks bearing sheathing bases; the leaflets are rhomboid to ovate with toothed margins, up to about 6 cm long and 4 cm broad. The inflorescence is a compound umbel of 4–12 mostly short rays bearing many small creamy-white to greenish-white flowers 2–3 mm across, with five sepals and five petals. The fruit is a schizocarp, broadly ovoid to almost globose, 1–1.5 mm long and ribbed; the seeds are small and brown. Celery is the type species of the genus Apium — the type genus of the family Apiaceae — in the order Apiales, giving it special taxonomic significance.

According to Kew POWO, the native range of Apium graveolens runs from Macaronesia (the Canary Islands, Madeira…) and North Africa through Europe to the Western Himalaya; it is a biennial of the temperate biome that favours cool, moist places. The wild form (often called 'smallage' or wild celery) grows in brackish marshes, on coasts and on damp ground, and is smaller, tougher and more bitter than the cultivated forms. Over thousands of years of selection, growers produced three main groups: stalk celery (var. dulce), grown for its fleshy leaf stalks; celeriac (var. rapaceum), grown for its swollen underground corm; and leaf celery (var. secalinum), grown for its leaves and used as a herb. Today celery is cultivated and naturalised across Europe, Asia, the Americas and Oceania. In Vietnam celery is a familiar northern vegetable that thrives in the cool season and is grown mainly in the winter–spring crop.

Chemically, celery contains three main groups of bioactives. The first is the phthalides — most notably 3-n-butylphthalide (NBP) and sedanolide — which give the characteristic aroma and are concentrated in the seed oil. The second is the flavonoids: celery is one of the vegetable sources richest in apigenin (as glycosides such as apiin) together with luteolin; these flavones are much studied for anti-inflammatory and antioxidant activity. The third group is the volatile oil, including limonene, selinene and linalool, together with furanocoumarins (psoralen, bergapten, xanthotoxin) and coumarins — the group responsible for photosensitivity. The stalks and corm are watery (about 90–95% water) and supply dietary fibre, mannitol, vitamins K and C, folate, and the minerals potassium, calcium and magnesium; celery seed yields 2–3% essential oil. Phthalide and essential-oil levels are far higher in the seed and in the wild form than in cultivated stalks.

Celery is used mainly as a vegetable and flavouring: in Vietnam celery stir-fried with beef and served with Nam Vang noodles is a familiar dish; celeriac is stewed and leaf celery flavours soups. Worldwide, celery forms the aromatic base of mirepoix/sofrito, features in salads and juices, and its seed is a spice, while celeriac is mashed or roasted. In traditional medicine celery and celery seed are used as a diuretic and for high blood pressure, gout, rheumatism and digestion. In research, a Wiley review (2024) concluded that celery's antihypertensive effect is linked to 3-n-butylphthalide and apigenin; work by Sohrabi et al. (2021) showed that celery-seed extract has a vasodilatory effect; and the review by Daoud et al. (2025) summarises its anti-inflammatory, antioxidant and antihypertensive activities. Notably, 3-n-butylphthalide isolated from celery seed has been developed into a medicine for ischaemic stroke in China, and in vivo/in vitro studies (Gao et al., 2025) continue to clarify the mechanisms of its phthalides and flavonoids.

As food, celery is safe for people at normal levels, low in calories and rich in fibre. However, its furanocoumarins (psoralen, bergapten) can cause photosensitive dermatitis — recorded in people who harvest and process celery (celery dermatitis). Celery is a common food allergen in Europe, linked to the celery–mugwort–spice syndrome and to birch-pollen allergy. Because it is rich in vitamin K, people taking anticoagulants (warfarin) should keep their intake steady; celery-seed oil and extract, being high in phthalides, are not recommended in pregnancy because they may stimulate the uterus, and high doses should not be taken long-term. On conservation, the species Apium graveolens has not been assessed globally on the IUCN Red List (NE) and is not listed in the CITES appendices; it is widely cultivated and not globally threatened, although the wild form has become rare in parts of its native range (for example in Britain) owing to the loss of coastal marshes and damp ground. Conservation priorities are maintaining local celery varieties and coastal wild-celery populations, which are valuable gene sources for disease resistance, salt tolerance and quality.