Plant Datasheet for Costus asplundii

Type collected 1956 by E. Asplund at 1000 meters Prov. Napo-Pastaza, Mera, edge of forest on shore of Rio Pastaza in Ecuador, Pastaza. Described as growing to 5 m high, flowers white, labellum with a large yellow blotch at base of middle lobe. Other collections are documented in other parts of southeastern Ecuador.

Atlanta Botanical Gardens #92-0790, specimen collected in 1992 in the Coca region of Ecuador by Atlanta Botanic Gardens. Has grown to about 8 ft tall in the greenhouse and conservatory. Has long pointed, narrow leaves with fuzzy undersides, slight purplish color, dark green color on top, dark purplish leaf sheath with prolific hairs near juncture of leaves. Horticulturalist at ABG does not recall this plant flowering. Visited Atlanta Bot Garden again in October 2002. Plant has been moved now to a location on the right side of conservatory, just before the first bridge. Plant is not nearly as tall as before. This appears to me to be Costus asplundii, but not certain as it has not flowered.

Plants that are common in cultivation are in a form with long narrow leaves that are deep purple on the undersides. This form is known to be very difficult to bring to flower. I have only seen it in flower one time, at Lyon Arboretum in Hawaii. The bracts on this plant do not match the description of the species as written by Paul Maas when he named it as Costus asplundii. It has dark red bracts and bract appendages, with only the lower appendages tinged in green. The flowers have an overall look of pink with pink corolla, white labellum tinged in pink with yellow throat. It does have the very wide calyx as described by Maas and the stigose hairs around the ligules.

In 2007, then again in 2009, and in 2015 I visited the area of the Rio Nangaritza in southeastern Ecuador, province of Zamora-Chinchipe. There is a plant that is very common in that watershed, growing in sunny areas along the roads and along the river. It has virtually colonized some areas where the forests have been cleared. The plant grows very tall, as much as 5 meters, is extremely hairy along the stems and ligules with long strigose hairs. The leaves are green both sides and wide - completely unlike the narrow leaves of the cultivated form of Costus asplundii. The bracts are all green in the exposed part with green appendages that are either horizontal or folded down. The covered part of the bracts is red. The calyx is not as wide as described for this species. The flowers are very large open type, with white corolla and white labellum with a yellow throat. In short, this plant looks nothing at all like the cultivated plant known to so many Costus growers, but it does match closely to Maas' description of Costus asplundii. SeePID 7528 for photos and details.

In 2016, Paul Maas reviewed some of my field observations on iNaturalist and informed me that the white fowered Costus I saw in Ecuador is Costus asplundii. After looking at the herbarium specimens and re-reading the description in Maas' monograph, I have now concluded that this plant from Rio Nangaritza is the species Costus asplundii. It is curious that it grows only along the Rio Nangaritza in Zamora Chinchipe, and was not seen farther to the north along the Rio Zamora valley.

ACCESSION NOTES:
R2254 was from Smithsonian USBG1994-702, did not survive. R3055 from Jim West's Reserva Rio Guaycuyacu, Ecuador, did not survive.

R2910, R2966 and R2976-77 all from cultivated plants in US horticulture. I have been growing them for many years but have never been able to bring them to flower. R2976 has been vouchered at the UC Berkeley, Jepsen Herbarium, UC2045834.

R3125 was collected near the Rio Mazon in amazonian Peru, has not flowered but vegetatively identical with long narrow leaves with purple undersides and hairs throughout. It grew for several years but finally died out. Propagules of this collection have been sent to John Mood, Hector Caratini, Bob Castro, and to the Hawaii Tropical Botanical Garden.

R3193 from near Gualaquiza in southeastern Ecuador has green narrow leaves and long hairs indicative of C. asplundii, but has not flowered. Was not seen in flower when collected.

OBSERVATION NOTES:

trail from Rio Mazán, Santa Teresa,Maynas Province, Peru, Latitude -3.54, Longitude -73.177, at 120 meters elevation.

GINGERSRUS CATALOG LISTING:
I won't lie to you, this plant is very difficult to bring to flower, but WOW! It is really spectacular when it does bloom. I have only seen it in flower one time, at Lyon Arboretum in Hawaii. The late Ray Baker of Lyon Arboretum was with me at the time and he told me he had never seen it in flower before either.

This plant is mostly grown for its foliage, narrow purple backed leaves, thick long hairs on the stems. I have collected seeds of this species in Peru and in Ecuador, and also have a specimen from US cultivation. It is not known whether the flowers will vary from these collections.