Flora of New Zealand Series

potato

Glabrate or hairy, unarmed perennial herb with rhizomes bearing large terminal tubers; stems to c. 1 m tall, ± winged, much-branched. Petiole to 10 cm long. Lvs to c. 40 cm long, imparipinnate; false stipules at base to c. 2 cm long, oblique or semi-lunate; main leaflets 5-9, variable, mainly stalked, glabrate or hairy, entire, with small, very unequal, broad leaflets between. Lamina of main leaflets usually to 12-(15) × 7-(8) cm, broad-ovate, elliptic-ovate or oblong-ovate; base ± cordate, often obliquely so; apex usually obtuse or acuminate with a blunt apex, sometimes acute. Cymes loose, with few-15 fls; peduncles long and slender, often > 12 cm long; pedicels deflexed at fruiting. Calyx 6-10 mm long, hairy; lobes lanceolate or linear-lanceolate, > tube, somewhat accrescent. Corolla 2-4 cm diam., white to mauve or purple; lobes triangular and undulate, reflexing, somewhat hairy outside, especially on margins. Anthers 6-9 mm long. Berry 1-3 cm diam., globose or subglobose, green; stone cells 0. Seeds c. 2 mm long, obovoid to ± ellipsoid.

N.; S.; St.; K., Ch., A., C.

Andes 1853

Commonly on waste land, rubbish dumps, around old dwellings, camp sites, and coastal beaches frequented by people.

FL Nov-Apr.

Potatoes are recorded or reported as having escaped from cultivation in many places but the sp. is rarely fully naturalised and is thus usually only a casual. Although they are one of the most important food plants in N.Z., the green parts, particularly tubers which have been exposed to light, have long been known to be toxic to humans and domestic stock (Connor 1977). The length of lvs and size of leaflets are often considerably more in cultivation than indicated above for wild plants.

Presumably, potatoes were first introduced to N.Z. by Captain Cook; since then many cvs have been brought in and later others raised locally. The earliest potato grown in N.Z., a type which is still occasionally grown or persists in old cultivation sites where it may be more or less wild, belongs to subsp. andigena (Juz. et Buk.) Hawkes. It mostly has purplish stems and corollas, as well as long purplish rhizomes and irregular, elongated, purple tubers. Many cvs grown today are derived from other types of potatoes and the above description only attempts to circumscribe the common ones which are likely to be wild. In addition to the 2-celled frs which are usual in the Solanaceae, S. tuberosum sometimes has 3-celled ones.