Origin and Habitat: Rio Negro region in Southern Argentina.

Description: Echinopsis melanopotamica which comes from the Rio Negro region in Southern Argentina represent the southern form of Echinopsis leucantha.
Similar species: It is related both with Echinopsis rhodotricha and Echinopsis ferox. But it is easily recognizable for its cylindrical stem and upper spines bent over the plant apex.
Habit: Plants solitary for a while but eventually may form clumps.
Stem: Globose to oblong, 25-100(130) cm tall.15-25 cm in diameter. Very dark green sometime greyish or purplish.
Ribs: 12-14, obtuse, somewhat compressed up to 1,5 cm tall.
Areoles: Close together, oblong.
Radial spines: About 6-8, orangish-yellow to dark brown, subulate, rigid, with a bulbous base, more or less curved, 1-2 cm long.
Central spines: 1 strong, curved, elongated, usually 3 cm long (but often up to 10 cm long)
Flowers: Funnel-form, up to 16 (or more) cm long, 10 cm in diameter, the tube about 3 cm broad at the mouth, dark brown, with scattered areoles bearing small tufts of brown hairs. Outer perianth segments brownish, spreading, 2 cm long, with an acute scarious tip. Inner perianth segment in about 3 series, spreading, the outer purplish, the inner ones white, oblong, acute approx 3 cm long. Filaments many of unequal length, the series at the mouth of the flower-tube erect up to 1,5 cm long. Stigma lobes numerous creamy-white to green.
Fruits: Orangish, dehiscent, pulp white.
Seeds: Black, up to 1,5 cm in diameter.

Cultivation and Propagation: The Echinopsis melanopotamicus is a summer grower species that offers no cultivation difficulties. Water regularly in summer (but do not overwater ) needs good drainage and very porous soil, keep rather dry in winter. Feed with a high potassium fertilizer in summer. It is quite frost resistant if kept dry (hardy to -10° C). Need a bright exposure, full sun or half shade in summer.
Propagation: Direct sow after last frost, offsets.
This is for one seed grown plant growing in a 6" inch container shipped bare root. All of our plants are grown in the beautiful Temecula Valley in sunny Southern California, and we ship within the United States. Shipping is done Monday thru Friday
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