Trichocereus Blog: Trichocereus Terscheckii (Echinopsis Terscheckii)

Trichocereus Terscheckii (Echinopsis Terscheckii Parmentier ex Pfeiffer)

Origin: The species Trichocereus Terscheckii contains a very wide variety of plants, of which some are very close to Trichocereus Pasacana (Echinopsis Pasacana). Trichocereus Terscheckii grows around the south of Bolivia, North Argentina (Catamarca, Tucuman, La Rioja, Jujuy, San Juan, Salta) and there are countless intermediates between Trichocereus Terscheckii, Trichocereus atacamensis, Trichocereus Pasacana and Trichocereus Validus. The latter is probably just one of those intermediate forms of Trichocereus Terscheckii anyway. Besides, the plant that was called Trichocereus Werdermannianus is actually an Intermediate form between Trichocereus Taquimbalensis and Trichocereus Terscheckii, though it is closer related to Taquimbalensis than Terscheckii. Overall, this is a very complex and highly controversial group of plants and only DNA testing can pin down the family tree that is hidden inside those beautiful tree-like plants. Personally, I think that all those Andean Trichocereus are members of a very variable group of plants that should all be merged. I will now add the description of Trichocereus Terscheckii, though there certainly are other forms of this plant that might be a little bit atypical. This is normal, because everywhere different species grow together, there will be natural hybrids and intermediate forms. I am not here to fix the mess that went down in the taxonomy of those plants in the past 100 years. I like those plants and I will use this page to portray the botanical variety that this species can have.

Synonyms: Echinopsis Terscheckii, Cereus Terscheckii, Pilosocereus Terscheckii, Cereus fulvispinus, Trichocereus Validus, Echinopsis Valida, Trichocereus Werdermannianus, Cereus werdermannianus, Echinopsis Werdermannianus, Cereus Validissimus. Besides, some forms of Trichocereus Pasacana and Trichocereus Tarijensis are synonymous with Trichocereus Terscheckii too.

Varieties: Trichocereus Terscheckiioides, Trichocereus Terscheckii var. Montanus,

Cultivation: Trichocereus Terscheckii is an amazing plant in culture. They grow very slow compared to other Trichos and don’t require a lot of water. I usually try to give them as much free root run as possible, what is important for their ability to flower. Their growth rate depends on many things, like how they are grown, hoch much water & fertilizer they get, and so on. Plants in habitat grow very slow and sometimes take 50 years to reach a good size because they get very little water and nutrients. Their mature form is totally different to what they look like as seedlings.

Description: They start off as a typical, columnar cactus but grow more branched later on in the life and sometimes get a couple of additional “arms”. Trichocereus Terscheckii can reach a size of 10-15 meters and a diameter of up to 60 centimeters.

Ribs: 8-15

Areoles: Approx. 2 centimeters in diameter and up to 3-4 centimeters apart from each other.

Spines: 10-16 spines, yellow and up to 10 centimeters long

Flower: White, 15-22 centimeters long, 14 centimeters wide, petals up to 8 centimeters. Tube covered with brown, wooly hair. The variety Trichocereus Montanus was said to be less branchy and grew more like a typical columnar. Besides it had a larger diameter. I personally do not accept any varieties because I think that this is just a crazily variable species.

Trichocereus Terscheckii and Frost: Trichocereus Terscheckii is quite cold hardy and even survives in some areas in the United States. Personally, I would recommend a minumum average temperature of 10° celsius/50 Fahrenheit, but they are known to survive short night frosts without a problem. However, temperatures should never go below -9°/15.8 Fahrenheit. It is also important to keep away rain and moisture during the cold months, because the rain is probably a bigger problem that the cold temperatures. Those plants can stand the cold, but as soon as it´s cold and wet, it´s starting to get dangerous.

Trichocereus Terscheckii from Seed: This species is very easy from seed. It requires the same conditions than other Trichocereus species, but keeping the seed cold over night can help to break up the dormancy. The seed is usually viable for many years and I am sure you can get some germinations as long as the seed does not get older than 10 years. But best germination rates usually are within the first year. Make sure not to sow out too many of them at once, because they become quite fat and need enough space.

Trichocereus Terscheckii Seed & live cutting sources: This plant sometimes shows up on Ebay as live cuttings, plants or seeds. Many seed sources are selling old seed, so make sure to ask about the age of the seed. The best seed is usually from the growers who have a plant in their garden and give away seed. But there are some commercial sellers, including Köhres, who sell seed. Havent tested their Terscheckii seed lately but I tested it years ago, and it was ok.