Aristea juncifolia is a slender, rhizomatous perennial that grows 6 to 11 cylindrical leaves. Small clusters of bright blue flowers without stalks grow spaced along the stem. Individual flowers are short-lived, mostly lasting for one day; more will open on sunny days, maximising the chances of pollination by picking the better conditions. Three yellow anthers can be seen in the flower centre. Brown bracts are found at each flower base. Flowering happens in late spring to early summer, often best in the year after a veld fire.
This plant grows in sandy soil along the southern coast and lower slopes of the Western Cape (Bean and Johns, 2005; Bond and Goldblatt, 1984; iSpot).