- Names also: Red Orach, Mountain Spinach, French Spinach
- Family: Amaranth family – Amaranthaceae (formerly Goosefoot Family – Chenopodiaceae)
- Growing form: Annual, unisexual, monoecious herb.
- Height: 50–120 cm (20–50 in.). Stem erect, sparsely branched, cylindrical, green-striped, base colour yellowish or sometimes reddish. Sometimes whole plant reddish brown.
- Flower: Flowers modest, unisexual. Staminate flowers with 5-lobed perianth. Stamens 5. Pistillate flowers lacking perianth, enclosed by 2 erect, mealy bracts, stalkless in the clustered flowers, stalked in singly-borne flowers. Bracts almost stalkless, round, net-veined, edges glossy. Styles 2. Inflorescence a spike-like, leafless–sparsely-leaved raceme.
- Leaves: Alternate, lowest almost opposite. Blade widely triangular, 4–9 cm (1.6– 3.6 in.) long, slightly mealy when young, lower leaves with sagittate or cordate base, with entire or sparely-toothed margins, upper leaves with rounded base, with entire margins.
- Fruit: Achene enclosed by fruit calyx. Calyx with two round, net-veined, entire margins, seperating leaves, 5–15 mm (0.2– 0.6 in.) wide. Seed brown–black, 1.5–3 mm (0.06–0.12 in.).
- Habitat: Gardens and rubbish tips. Left-over from old gardens.
- Flowering time: July–August.
Genus Atriplex is a difficult group from the point of view of identifying the species. The genus is easily confused with genus Chenopodium, but they can be told apart by the fact that Atriplex species are unisexual (monoecious or sometimes dioecious) but Chenopodium species are bisexual and the former’s fruits typically have 2 partly joined bracteoles (Chenopodium species do not). The characteristics of these bracteoles are important for identifying the species within genus Atriplex. Garden orache is one of the best at thriving on culturally-influenced land. It used to be cultivated and used like spinach.
Garden orache is quite like hoary orache, although the latter’s leaves have sharper corners and are glossy on top and paler below. Garden orache’s leaves are the same colour on both sides. Oraches’ leaves are usually opposite but garden orache’s leaves are usually alternate.