Flora of New Zealand Series

horseradish

Perennial arising from stout white fusiform roots. Stems stout, erect, grooved, branched above, to 130 cm tall. Rosette lvs elliptic to ovate to oblong, crenate or serrate; lamina (5)-10-30-(50) × 4-10-(15) cm; petiole 5-20-(50) cm long. Lower stem lvs similar in size and outline, but often deeply pinnatifid; upper stem lvs sessile, linear-lanceolate, toothed or entire, 4-12-(20) × 0.5-1-(3) cm. Panicle to 35 cm long; lateral axillary racemes to 20 cm long. Sepals 2-3 × 1-1.5 mm. Petals 4-5 ×2 mm. Silicle abortive, narrow-cylindric, 2-3 mm long.

N.; S.: probably throughout.

Europe 1864

Waste places, rubbish tips and drains.

FL Nov-Dec.

Horseradish is a garden discard which may persist for a long time, but apparently does not reproduce by seed in N.Z. The sp. has also been referred to in N.Z. as Cochlearia armoracia and as Nasturtium armoracia.