A researched TAFE plant identification study record for Tagetes lemmonii. The teacher's common name “Passionfruit Marigold” is retained; Copper Canyon Daisy and Mt Lemmon Marigold are also widely used.

Identification

Unlike the compact annual marigolds commonly sold for bedding, this species forms a substantial aromatic shrub. Fine, divided green leaves release a strong citrus, marigold or passionfruit-like scent when brushed. Branch tips carry many clear-yellow, single daisy-like heads. The combination of woody habit, dissected pungent foliage and late-season flowering is diagnostic.

Distribution and flowering response

Kew records the native range from southern Arizona into Chihuahua and Sonora in northern Mexico, primarily in desert or dry-shrubland biomes. Flowering responds strongly to short day length: displays are usually heaviest in autumn and can continue into winter in mild climates, while cloudy periods may also influence timing.

Cultivation

Grow in full sun or light part shade in sharply drained soil. Once established it is drought tolerant; deep, spaced watering is safer than constantly wet soil. Prune after the major flowering display to contain size and renew branching. In frost-prone locations, delay hard renovation until the risk of damaging cold has passed.

Study note

Common names are inconsistent and overlap with unrelated or annual “marigolds”. Always record the botanical name. The strong foliage oils may be unpleasant or irritating to sensitive people, so gloves and good ventilation are reasonable when pruning large amounts.