Echinopsis terscheckii, commonly known as the cardon grande cactus or Argentine saguaro, is a large cactus native to South America and popular in cultivation. It is a columnar, branching cactus that can grow over 7.6 metres (25 ft) tall.
Its branches are about 25 cm (9.8 in) in diameter with 8 to 14 ribs. It has large brownish areoles about 2.5 cm (0.98 in) apart with 8 to 15 yellowish spines, 8.3–10 cm (3.27–3.9 in) long. The nocturnal white flowers can grow up to 20 cm (7.9 in) long and 13–15 cm (5.1–5.9 in) wide. The round or oblong blue fruits are about 1.3 cm (0.51 in) in diameter and contain black, oval seeds approximately 0.76 mm (0.030 in) long.