Trichocereus glaucus, also known as Echinopsis glauca, is a Peruvian Trichocereus species described by Friedrich Ritter. It might be synonymous with Trichocereus chalaensis, or at least related to it in some form. There are also Peruvianoids that are sold under this name and I occasionally encountered Trichocereus fulvilanus being sold under this name as well. The whole complex is chaotic and it´s hard to verify which plant Ritter´s description was covering.
Trichocereus glaucus – Foto: Friedrich Ritter
Origin of Trichocereus glaucus:
Peru ( South Peru ), Arequipa (Rio Tambo), Chile. In Chile, this plant is closely related to Trichocereus fulvilanus and Trichocereus deserticolus.
Description of Trichocereus glaucus / Echinopsis glauca:
Trichocereus glaucuscan get between 1,5-2 meters tall and is a prostrate/creeping species that you often find hanging down slopes and cliffs. This trait is very distinct in the variety Trichocereus glaucus var. pendens. The color of the skin is very glaucous and small specimens look absolutely like the type of plants that are labeled Trichocereus macrogonus / Echinopsis macrogona today. Spiny, dark blue versions from the complex around T. peruvianus. However, macrogonus grows columnar while this species tends to bend over with age. New growth is very glaucous.
Areoles of Echinopsis glauca:
The areoles are dark brown to gray in color and approximately 2,5 centimeters apart of each other. Similar to other plants related to Trichocereus peruvianus, the plant has a diameter of up to 10 centimeters and the areoles are gray felted. The spines look a bit like the ones on Trichocereus cuzcoensisand old growth has a typical satin white glow that is common on this species. Trichocereus glaucus has 6-9 ribs, 3-6 middle spines and 8-11 radial spines. The middle spines are 5-10 centimeters and the radial spines 1-2 centimeters long. New spine growth is black to brown and turns gray with age.
Flowers of T. glaucus:
White, just like almost every other Trichocereus from this complex. The diameter is very variable and usually is between 15-22 centimeters. Trichocereus glaucus is a night-flowering species with green, round fruits. However, the hairy flowers usually stay open until the next morning.
Fruit of E. glauca:
Round, green, and 3 centimeters thick.
Type locality: Lower part of the Rio Tambo in the department Arequipa.
Trichocereus glaucus is very similar to Trichocereus chalaensisand grows in a similar way. We think that Trichocereus chalaensis might be synonymous with Ritter´s Trichocereus glaucus. Ritter´s field number of Trichocereus glaucus was FR270. We distributed seeds of Trichocereus glaucus various times in the past and all ended up amazingly beautiful. It´s a very nice species.
Buy Trichocereus glaucus seeds:
Trichocereus glaucus aka Echinopsis glauca is extremely rare and most plants on the market will probably come labeled as “Trichocereus peruvianus” or “Trichocereus macrogonus”. It is common occurence for some Peruvian cactus collectors to label all glaucous Trichocereus species with this name. This is obviously wrong and causes chaos. We sometimes have plants of this species in our Trichocereus Facebook group, which can be found here: https://facebook.com/groups/trichocereus
Cultivation of Echinopsis glauca:
Trichocereus glaucus is a very resilient grower and likes to be watered well in summer. In winter, they should be kept as dry as possible at around 10° Celsius. Seed germinates very well and the plant is usually very tough. That´s also caused by its drought tolerance, which is very typical for these kinds of plants. The species will probably tolerate temperatures between -5° to -7° Celsius over very short time, but I would not stress it and this also depends on many other factors, like general health and dryness. I would recommend keeping at no lower than 10° Celsius in winter.
Varieties of E. glauca: Trichocereus glaucus var. pendens. This variety does only grow hanging down cliffs and small hills. This variety only grows at one location in Chile and is extremely rare. This local population is in the south of Arica, Camarca in Chile. Backeberg suggested that this would be his Trichocereus uyumpaensis, but Friedrich Ritter vehemently disagreed with that. More information is necessary about this topic.
Below: Trichocereus Glaucus – Fotos: Auxin
Translation of Ritter´s description (loosely)
This species forms shrubs the size of 1 – 2 meters and often several meters in diameter, sprouting mainly from shoots that lay sideways on the ground. This plant rarely pups from the top or upper parts. The shoots are 5 – 8 inches thick, erect, later lying in the lower parts, the new shoot blue-green, later gray-green.
Ribs: 7-9, very broad, obtuse, 7.5 to 13 mm high, 15-25 mm wide, notched, with transverse furrows that do not reach down to the separating grooves of the ribs, areoles: grey felted, 1/2-3/4 inches in diameter, 1 to 2 inches free removal, let down by the humps in the notches Spines: In the new shoot black to brown, becoming gray, straight, rigid Marginal spines: 7-10, directed laterally, the lower and lateral 8 to 15 mm long, coarse needle-shaped, somewhat flattened, the upper the upper stronger and not sharply separated from the Central spines. Central spines: 3-6, very spread apart, subulate in the middle, but usually closer to the top edge and almost in the position of an edge of spine, below 1.5 mm thick Flower: Not far from the apex, 13 to 19 centimeters long, fragrant, opening in the evening, the morning still open, Ovary: Green with fleshy green, narrowly triangular, 2-5 mm long, pointed scales and large scales raised bases. The flowers are covered with brown/black hairs. Partition against the nectar chamber 3-4 mm thick, tube-shaped, 13 to 23 mm long, to the stylus 1to 2 mm wide, brownish, almost openly, with nectar
In addition funnel shaped, 40-65 mm long, the top 2 to 3 cm wide, pale green interior, exterior gray-green, with triangular points, 7.5 to 10 mm long, dark green scales and tufts of hair as on the ovary. Stamens: white, greenish below, insertions missing on the top 2 to 3 centimeters of the tube to a ring on the hem, pouch pale brown, approximately at half height petals standing Stylus: pale green, white or pale brownish above, 10 to 11 cm in length, with 14 to 18 mm fall on the 13-16 spread pale yellow stigma lobes, between the pouches or outstanding.
German original description / Deutsche Original Beschreibung:
Büsche von 1 meter bis 2 meter höhe und oft mehreren Metern Durchmesser, sprossend hauptsächlich unten von liegenden Trieben, weniger oben sprossend. Triebe 5 bis 8 Zentimeter dick, aufrecht, später in den unteren Teilen liegend, im Neutrieb blaugrün, später mehr graugrün. Rippen: 7-9, sehr breit, stumpf, 7,5 bis 13 mm hoch, 15 bis 25 mm breit, gekerbt, mit Querfurchen, die nicht bis zu den Trennfurchen der Rippen hinabreichen, Areolen: Graufilzig, 1/2-3/4 Zentimeter Durchmesser, 1bis 2 Zentimeter freie Entfernung, , von den Höckern in die Kerben hinabreichend Stacheln: Im Neutrieb schwarz bis braun, , vergrauend, gerade, starr Randstacheln: 7 bis 10, seitlich gerichtet, die unteren und seitlichen 8 bis 15 mm lang, derb nadelförmig, etwas abgeflacht, die oberen die Oberen stärker und nicht scharf von den Mittelstacheln gesondert. Mittelstacheln: 3 bis 6, sehr gespreizt, pfriemlich in der Mitte, aber meist näher dem oberen Rand und fast in der Stellung eines Randstachels, unten 1,5 mm dick Blüte: Nicht weit weg vom Scheitel, 13 bis 19 zentimeter lang, duftend, abends öffnend, morgens noch offen, Fruchtknoten: Grün mit fleischigen grünen, schmal dreieckigen, 2-5 mm langen spitzen Schuppen und großen erhabenen Schuppenbasen. Mit starken schwarzen oder braunschwarzen Wollhaaren. Trennwand gegen die Nektarkammer 3-4 mm dick, diese tubisch, 13 bis 23 mm lang,um den Griffel 1bis 2 mm weit, bräunlich, fast offen, mit Nektar
Röhren: Darüber trichterig, 40 bis 65 mm lang, oben 2 bis 3 cm weit, innen blaß grünlich , außen graugrün, mit dreieckigen Spitzen, 7,5 bis 10 mm langen dunkelgrünen Schuppen und Haarbüscheln wie auf dem Fruchtknoten. Staubfäden: weiß, unten grünlich, Insertionen fehlen auf den obersten 2 bis 3 Zentimetern der Röhre, bis auf einen Ring auf dem Saum, Beutel blassbraun, etwa bei halber Petalen Höhe stehend Griffel: blassgrün, oben weiß oder blass bräunlich, 10 bis 11 cm lang, wovon 14 bis 18 mm auf die 13-16 gespreizten blaßgelben Narbenäste fallen, zwischen den Beuteln oder sie überragend.
Photos of Trichocereus glaucus / Echinopsis glauca
In comparison to this species, check out closely related species:
Trichocereus santaensisis columnar cactus and species described by Curt Backeberg and Werner Rauh. It is endemic to the Santa Valley in Peru. There are many different forms that belong into the larger context of T. santaensis, e.g. Trichocereus sp. Chavin de Huantar also known as El Lanzon, Trichocereus huanucoensis, Trichocereus pallarensis and many others. The current status of Trichocereus santaensis is unclear. The spiny populations might be placed into Trichocereus peruvianus, and the classic ones from Rio Santa might be placed into Trichocereus pachanoi. Without genetic testing it will be hard to estimate if Trichocereus santaensis is a valid species or just another Backeberg name.
Origin of Trichocereus santaensis
Northern Peru, the valley around the Rio Santa, Puente, Bedoya, Huayanca
Can be kept apart from Trichocereus cuzcoensis by the absence of swollen spine bases. It also has a more frosted blue skin color, has fewer spines and shorter middle spines. Unlike Trichocereus peruvianus, it grows always columnar and does not grow prostrate.
Trichocereus Santaensis – Huntington Botanical Garden – by Richard Hipp!
Description of Trichocereus santaensis Rauh & backb g -. Descr. Cact. Nov. 20, 1956
Trichocereus santaensis can get up to five meters high and branches from the bottom. The stems are blue-green to a glaucous green. It has 7-9 ribs that are similarly broad than the ones on Trichocereus knuthianus aka Echinopsis knuthiana. There is a distinct furrow above the areoles. This distinct V-Notch is very strong in young pups. The areoles have a diameter of approximately 1 centimeter and Trichocereus santaensis has between 1-3 radial spines. Spines medium long to short. In addition, Trichocereus santaensis has one very long middle spine, which is up to 5 centimeters long.
Flower: The flower is white and gets up to 22 centimeters in length. It has a similar flower than other San Pedro types, which is another indicator that Trichocereus santaensis is just a regional form of another species, e.g. T. pachanoi or T. peruvianus.
Origin/Habitat: Rio Santa, Puente, Huayacana, Bedoya.
Trichocereus santaensis is very similar to Trichocereus cuzcoensis and is constantly confused with it. However, it does NOT have rounded, knobby spine bases. Besides, the spination is less strong and grows always columnar instead of creeping. Today, the species would probably not be considered to be correct and extensive DNA testing is necessary to look into the limits of this species and where other species begin.
Please note that T. santaensis is very variable due to the high number of regional forms. Some of which have red spines, some with yellow spines and some where the spines are completely absent.
In the Chapter of Trichocereus peruvianus, Backeberg wrote about its growth type:
This is Backebergs Key for Trichocereus santaensis
Branchesto 10cm∅ Blue greenshoots Ribs7, very broad, strongly furrowed, Notflattenedfurrows Spinesgray-brown,brighter towards the base Middlespines: 1 spine is longer, spines up to 4 cmlong.
Friedrich Ritter´s description of Trichocereus santaensis
TrichocereusSANTAENSISRAUH&BACKBG. 1956RAUH: BEITRÄGE PERUANISCHER KAKTEENVEGETATION 1958, s. 361 Differences from TR. Pachanoi (data for the latter in parentheses): Body gray-green (grass green to bluish green). Ri. 6-7, usually 6 (5-8, in Peru medium to 10 and even higher), on the Areoles a slight v-shaped Notch (little cross notch). Ar. 3-5 mm Dm Spines: few or absent,Rsp. to 3, a few mm to 3 cm long, Middle Spines. usually one, often it is the only Spine, a few mm to 4 cm long. Flower. Near the apex, about 18-19 cm long, about 12 cm wide open (up to 20 cm wide between the outer petals), obliquely upward (about protruding horizontally), just (with two slight curves). Nectar Chamber 19 mm long (slightly longer), without significant gap (small space), with little or no Nectar (with some nectar). Tube about ca 6 cm long with 2.5 cm further Opening (longer and wider). Petals slightly shorter and narrower, the outer almost adjacent to the interior Ones (strongly bent outwards), SANTA Valley at 2000 m and about Depart. Ancash; only here. No. FR 567a. Fig. 1,188,
Trichocereus santaensis / Echinopsis santaensis at the Rio Santa (Riley Flatten)
Photos below Trichocereus santaensis / Echinopsis santaensis in Chavin de Huantar, El Lanzon (Riley Flatten)
In this chapter I want to show you some of the wild populations of Echinopsis macrogona from Matucana. The species is partially synonymous with Echinopsis peruviana, which is why there is quite some overlay between these two. The name Echinopsis macrogona has a long and troubled history, because most authors have their own opinion about it. Personally, I consider the name Cereus macrogonus (which resulted in later descriptions as Trichocereus macrogonus and Echinopsis macrogona) to be too problematic to count. Its original description lacks information on crucial details such as the country of origin and this leads to the massive confusion surrounding it. Seed sellers carry various species under the name, e.g. Echinopsis peruviana, Echinopsis pachanoi, Trichocereus werdermannianus (currently seen as form of Echinopsis terscheckii), Trichocereus taquimbalensis, Trichocereus tacaquirensis, Echinopsis lageniformis/ Trichocereus bridgesii, Trichocereus santaensis, Trichocereus terscheckii, Trichocereus schoenii, etc. There´s almost no species that this name hasn´t been slapped on, which makes comparisons between plants from the commercial market completely pointless. If I would get a Dollar every time someone tells me that “x plant can´t be Trichocereus macrogonus because they seed grown plant looks completely different” I would be a made man.
How to differentiate Trichocereus macrogonus / Echinopsis macrogona and Trichocereus peruvianus / Echinopsis peruviana?
In this article we show some photos from Matucana, which is the type locality of Echinopsis peruviana. These plants are often referred to as Trichocereus macrogonus and people who identify these plants tend to identify them as Trichocereus macrogonus due to their spine color. I personally do not think it makes a lot of sense to differentiate between Echinopsis peruviana and Echinopsis macrogona as the whole complex is incredibly variable. Differences between a form from Matucana and one from another Peruvian city do not mean that something has to be a different species. The people who get to choose which differences draw clear lines between two related species are the authors who describe them, and so far I have not read a conclusive argumentation on clear boundaries between Echinopsis macrogona and Echinopsis peruviana and I think DNA testing is the one tool that should be used to decide this. However, since there is no country of origin, type locality or Herbarium piece of the original Cereus macrogonus, which makes it impossible to compare other populations against it. And this is pretty much the crux of the problem.
Echinopsis macrogona / Trichocereus macrogonus Huariquina in Matucana
Below you can see some photos from Huariquina in Matucana. All plants there are very beautiful and among the most visually pleasing Trichocereus species we know. Icaro DNA and Los Gentiles look very much like this. The plants grow columnar, but with a clear tendency to lean over every now and then. They do not really grow prostrate, but they don´t always grow a 100% columnar either.
If you like the articles we write, check out some of our other ones:
Pomolargo is another Peruvianus population that is a glowing example for the beauty of this species.
Echinopsis macrogona / Trichocereus macrogonus Collana Roja in Matucana
Collana Roja is another Matucana population that is typical for Echinopsis macrogona. The spines are brow, sometimes even red, and this is one of the only traits that are somewhat usable to differentiate between Echinopsis peruviana and Echinopsis macrogona. Again, most are mostly synonymous anyways, which is underlined through the fact that Echinopsis macrogona was never found again, from the time on that Britton and Rose wrote their description of Trichocereus peruvianus. That alone speaks volumes and the reason is that all the plants which were formerly identified as Cereus macrogonus were later attributed to Britton and Rose´s name. There are differences between the two descriptions, but they are rather small-
Copyright: Chavin Herbalists
Echinopsis macrogona / Trichocereus macrogonus Collana Pichu in Matucana
Collana Pichu is very similar in regards to the phenotype and gets very close to Collana Roja.
Copyright: Chavin Herbalists
Echinopsis macrogona / Trichocereus macrogonus Sucro in Matucana
In Sucro we´ve seen some plants that were relatively short spined or even spineless. There´s quite a few regional forms of this species that is spineless, but these plants are usually very spiny as seedlings and only lose their spines later on. In particular, we´ve grown some seeds of Collana Roja, which are quite spiny as seedlings and we hope they will lose their spines later on.
Trichocereus peruvianus or Echinopsis peruvianais a columnar cactus that can get up to 4 meters long and reaches 20 centimeters in diameter. It´s also called the PERUVIAN TORCH cactus and is native in Peru. Britton and Rose – The Cact. II, S.136 /192
Most regional forms belonging to this species have a frosted blue color and grow between 6-9 ribs. Its flowers are white, though there are some close relatives that have a different flower color (Trichocereus tulhuayacensis). It usually grows upright, but sometimes grows prostrate hanging down from cliffs and rocks. The size and color of the spines varies greatly, but most of them have about 6-8 honey-colored to brown spines that can reach about 4 centimeters in length. The areoles are brown to beige-felted and up to 2,5 centimeters distanced from each other. The Spines do NOT have a knobbed Base. The spine color is one of the key traits if you attempt to tell it apart from Trichocereus macrogonus. We write more on Trichocereus macrogonus in that particular chapter.
A Peru at the type locality in Matucana.
Echinopsis peruviana flowers very easily as soon as it reaches a certain size and the plant is very easy to cultivate. Some of them have a distinct V-Notch above the areoles, but not all and it´s not a trait that is reliable for identification.
Cultivation of Trichocereus peruvianus / Echinopsis peruviana:
Trichocereus peruvianus can be grown from seed 0r propagated by cuttings. Seeds need to be sprinkled on top of the soil because they require sunlight to germinate. The seeds are tiny and only a few mm large and have a long viability. Usually, the seeds can stay viable for up to 10 years or above, though that depends on many factors. The Seed needs to be stored in a dry and cold environment to guarantee maximum viability.
Los Gentiles (Noah Reams)
The cactus can also be propagated through cuttings and it´s very easy to root. But make sure that the cuttings are not smaller than 20 centimeters because that stunts the growth tremendously.
The flower of Trichocereus peruvianus / Echinopsis peruviana:
The flower is white and reaches as size of up to 25 centimeters. Trichocereus peruvianus is a night flowering species.
Type locality of Trichocereus peruvianus / Echinopsis peruviana:
Peru (around Matucana). Trichocereus peruvianus is the dominant Trichocereus species in Matucana.
Plants that are closely related or are synonymous with Trichocereus peruvianus:
Trichocereus tacnaensis, Trichocereus puquiensis, Trichocereus santaensis (some of the plants around the Santa Valley belong to Tr. pachanoi though), Trichocereus tarmaensis (closely related to Trichocereus cuzcoensis as well), Trichocereus macrogonus, Echinopsis macrogona, Trichocereus f. Ancash, Trichocereus sp. Ayacucho, Trichocereus giganteus, Trichocereus longispinus, Trichocereus sp. Pamacoche, Trichocereus sp. Matucana, Trichocereus rosei,
Trichocereus peruvianus and Trichocereus pachanoiare sister species and closely related. Some field botanist considered them one large and variable species and there are countless intermediates and hybrids that could be placed in either species. Around 1950-1980, some authors came up with a large number of unnecessary species names and most of these plants would fit into the description of Trichocereus peruvianus as well.
Some commercial names that we sometimes see in combination with Trichocereus peruvianus.
Please note that these are not officially accepted varieties and we only list them in this form because they were listed by wholesale:
Trichocereus peruvianus var. (H14192), Huntington, EE.UU. Trichocereus peruvianus var. huancabamba, Piura, northwest Peru. Trichocereus peruvianus var. huancavelica (KK242a), west central Peru. Trichocereus peruvianus var. cuzcoensis (KK340), Huachac, Cuzco, southeastern Peru. Trichocereus peruvianus var. huancayo (KK338), west central Peru. Trichocereus peruvianus var. ancash (KK1688), San Marcos, Ancash, northwest Peru. Trichocereus peruvianus var. matucana (KK242) Lima, central west Peru. Trichocereus peruvianus var. puquiensis (KK1689), Puquio, Apurimac Region, southwestern peru. Trichocereus peruvianus var. trujilloensis, Trujillo, La Libertad, northwestern Peru. Trichocereus peruvianus var. tarmensis (KK2148), Tarma, Junin, west central Peru. Trichocereus peruvianus var. Rio Lurin (KK2147), Rio Rimac, Lima, west central Peru. Trichocereus peruvianus var. ayacuchensis (KK2151), southwestern Peru. Trichocereus peruvianus var. huaraz (KK2152), Ancash, northwestern Peru.
Culture of T. peruvianus:
The culture of Trichocereus peruvianus is not very hard. The plant has very similar requirements as other Trichocereus species like Trichocereus macrogonus or Trichocereus pachanoi. Trichocereus peruvianus is an extremely frost resistant plant that can thrive in the most difficult environment. Some of its forms grow columnar while some others are creeping/prostrate. In their natural habitats, they even hang down on hills or rocky slopes. When watering cacti, the soil should not stay wet for more than a couple of hours because it greatly increases the probability of rot. Cacti need a substrate that dries out fast and too much water is often deadly for them. Apart from a little bit of water here and there, you should only water Trichocereus peruvianus when it´s warm. During the hot growth-season, they can take daily or weekly watering and like to be fertilized on a 7-14-days schedule. I even fertilize weekly during the main season, but that also depends on your personal way of growing cacti. It’s best to use a mineral substrate like Pumice or Lava, with additives like Coir, Sand, Sowing Soil, Expanded Clay etc. Just make sure to add in a very small part of Coir or Humus because it helps to solidify the soil and increases the cactus ability to take in nutrients. I personally love Lava and Pumice and the plants enjoy it very much! Echinopsis peruviana aka Trichocereus peruvianus likes a sunny place in half-shade, but not full sun. They can take it if they are used to it, but it increases the risk of sunburn. Especially directly after the winter period when they are not used to it yet.
Winter & Frost Protection: Trichocereus peruvianus is a relatively frost hardy cactus. It’s usually not a problem for it to take take a little night frost here and there and is tolerant down to -9° Celsius. But that’s really the limit and I would not be comfortable to push it below that. There are always plants are less frost tolerant than others and you never know where the limit for your plant is going to be. A plant that spent its life in a heated greenhouse, will die very soon if you suddenly start exposing it to cold winter frost. The cacti need to be hardened up and in a good general health. In my greenhouse I overwinter Trichocereus at 1° Celsius between December and March.
Minimum average winter temperature:
The ideal average winter temperature for Trichocereus peruvianus is 10° Celsius. That´s close to their natural winter period in habitat. Trichocereus peruvianus can compensate short frosts down to 15.8° Fahrenheit every now and then but you should take care that it has an average temperature of around 50° Fahrenheit.
Winter storage & Winter Protection for Trichocereus:
Trichocereus peruvianus needs fresh air during the wintertime if you want to overwinter the plant inside. It also needs light and the soil has to be completely dry, to make sure that the rootstock does not rot. This is important because that’s exactly what happens in the habitat during the winter time. Trichocereus peruvianus can deal with low temperatures as long as its dry. Of course all those overwintering-rules only apply of you live in a country with hard winter frost down to -20° celsius and lower. If you live in a warmer country such as Australia, this certainly is not a problem for you and water or high air humidity are the bigger problem then. I also know many growers from the CA area in the USA, and they usually get their plants over the winter without problems, if they do nor get surprisingly cold frosts. Leave your Trichocereus peruvianus in a bright room, give it a little bit fresh air every now and then and make sure to keep the temperatures below 10° Celsius. As soon as you put them in a heated room, they will require regular waterings and light or they will die quickly. In addition they will etiolate. If kept dry, the water requirements during the winter are minimal though. The minimum temp in Fahrenheit is 50° Fahrenheit. No water should be given between late autumn (October-early May) unless you grow them in a heated place, eg greenhouse or house. If you are lucky enough to have a greenhouse, you can take out most Trichocereus in early March, but you should also check the maximum frost tolerance of the species you take out. There are many cacti that need higher temperatures to stay healthy.
Germinating Trichocereus peruvianus seeds:
Just like Seed of other Trichocereus species, Trichocereus peruvianus seeds need light to germinate. I usually prepare a mix of Pumice, Lava, Coir, and Sand and and sprinkle the seeds on top of the soil. Make sure not to knock off the sowing container/pot because that would probably bury the seeds and that’s never a good thing. Buried seeds often do not germinate due to the lacking light or they germinate deep inside the soil and die. So yeah, sprinkle them on top of the soil and make sure that the temperatures are between 26° and 30° Celsius. Make sure to add in enough water to start the germination process. However, it does not take a lot of water to kick start the germination and it’s always better to give very little water early on because you can always add in some more. But if you add too much water in the beginning, it cannot be undone without risking to wash or soak away the seed with the excess water. With a syringe, excess water can be removed from the sowing container. Put the sowing containers in a bright and warm place and be patient. A window sill works perfectly. You can also use a LED lamp to give them enough light to germinate and I can recommend that very much because it increases the germination rate. Adding a decent LED Lamp (like 100 Watt and above) will increase germination rates dramatically and the plants are healthier and grow faster.
Germination of seeds and why some seeds don’t germinate
The problem with seeds is that some shops resell seed from South America wholesalers that sell over-aged seed. So the shops might not know about the bad germination rates that their seeds have and that´s a real problem with Trichocereus peruvianus seed on the market. If you did everything I just mentioned and your seed does not germinate within like 2-6 weeks, it´s most likely old garbage. It does not help to keep it wet for longer than that because that’s not how germination of cactus seeds works. Instead, you let it dry and start another cycle once the soil is completely dry. It does not help to keep dead seed in germination chambers for 6+ weeks. You will just grow Algae and Moss. Another problem that you can get with commercial seed is that there´s a lot of misidentified seeds of this species available on the market. The people who collect these seeds usually don´t have access to literature and that´s why the misidentification rate is extremely high. . Many Trichocereus cuzcoensis are sold as Trichocereus peruvianus and that´s a big problem for the seed market.
My best recommendation is that if you can get in touch with the seed producer, send them a message and ask about a pic of the mother plant. That way, you can minimize the risk of getting mislabeled seed.
Seed Viability of Echinopsis peruviana/ Trichocereus peruvianus:
The seed of Trichocereus peruvianus is viable for many, many years. I sometimes successfully germinate seeds that are more than 5-10 years old but it always depends on the storage and the seed. Some are dead within a couple of months while some can even stay viable for decades, like Ariocarpus seeds. The bigger the seed, the longer they are viable btw. Rebutia are dead within a couple of weeks, Trichocereus & Echinopsis 5-10 years, Ariocarpus 10+ years, Echinocereus (5-10 years), Lophophora (2-5 years at max).
How to differentiate Trichocereus peruvianus and Trichocereus cuzcoensis?
The swollen spine bases of Trichocereus cuzcoensis are the main trait that Britton and Rose used to tell them apart. Trichocereus peruvianus does NOT have swollen spine bases. There are many intermediates and forms in between the two, but in regards to the original description that’s the most important trait. In addition, Trichocereus cuzcoensis only grows in Cuzco. There are relatives of Trichocereus cuzcoensis that can be found in other parts of Peru however, e.g. Trichocereus knuthianus, Trichocereus schoenii, etc
How to differentiate Trichocereus peruvianus and macrogonus
Both species are probably synonymous. Trichocereus macrogonus was used for plants with dark brown or red spines, while plants with different spine color were seen as Trichocereus peruvianus. The original description of Trichocereus macrogonus is ancient, lacked important traits or information such as country of origin and the original plant was never found again afterwards. Technically, Trichocereus macrogonus is the older name and might replace Trichocereus peruvianus as official name one day (IF the problematic description will be accepted). Some authors have already started to use this system, but is unclear if it will be accepted officially. Modern taxonomy moves towards fewer species, with a larger number of subspecies or varieties and I completely support that.
Trichocereus peruvianus from Lurin Valle / Lurin Valley
Trichocereus peruvianus from Ayacucho
Trichocereus peruvianus intermediate
Trichocereus peruvianus Apurimac KK1689
Trichocereus peruvianus ‘Rosei 1’ (Rodni Kisar)
Backeberg´s Description of Trichocereus peruvianus
Trichocereus peruvianus Br. & R. — The Cact., II : 136. 1920 Cereusrosei Werd., in Backeberg, „Neue Kakteen“, 101. 1931. Entweder ± aufrecht oder überliegend bis hängend, 2—4 m lang; Tr. bis 20 cm ∅, anfangs bereift; Rippen über den Areolen etwas eingesenkt und ± höckerig erscheinend, breit-rund; Areolen bis 2,5 cm entfernt, ziemlich groß, braunfilzig; St. zuerstbraun, ca. 10, einigebis 4 cm lang, stark undsteif, Basis nicht verdickt; Bl. weiß, groß, zum Teil zahlreich nach dem Scheitel zu entwickelt. — P e r u (bei Matucana; nach Rauh bis oberhalb von Matucana bzw. bei Tamboraque ander Lima—Oroya-Bahn bis auf 2800 m) (Abb. 1059—1060, Tafel 76). Britton u. Rose bilden mit ihrer Fig. 197 einenbaumartigaufrechten Cereus ab, Rauh dagegen einen hängenden; ichselbstfand die Art anfangs ± aufrecht, dann überliegend bisniederliegend. Es kommenbei Matucana aber auch Exemplare des aufrechten T. santaensisvor, den Britton u. Rose wohlnicht als besondere Art erkannten. Die Identifizierung dieser Art mit Tr. macrogonus (Kkde., 20. 1941) kann ich nicht aufrechterhalten.
Friedrich Ritter´s Description
T R I C H O C E R E U S (BERGER) RICCOBONO 1909 TRICHOCEREUS PACHANOI BR. & R. 1920 The Cactaceae, Bd. 2, S. 134 und TRICHOCEREUS PACHANOI FORMA PERUVIANUS RITT. comb. nov. syn. TRICHOCEREUS PERUVIANUS BR. & R. 1920 The Cactaceae, Bd. 2, S. 136 Für TRICHOCER. PACHANOI geben BR. & R. als Typusort an CUENCA, Ecuador, für TRICHOCER. PERUVIANUS MATUCANA, Peru. In Wahrheit liegtnur eine Art vor. ROSE war jedenfalls ungenügend orientiert Über die große Variationsbreitedieser Art in Bestachlung und Areolengröße. Man kann TRICHOCER. PERUVIANUS nur als eine Form der PACHANOI ansehen, die entweder allein oder mit letzterer an gleichen Stellen wächst von Ecuador bis Mittelperu, und zwar mit Übergangsformen in einander. Für die Form PACHANOI sind typisch Ar. von 3-5 mm Dm., feine Rst. vonwenigen mm Länge und meist nur 1 Mst. von wenigen mm bis zu etwa 2 cm Länge. Oft fehlen die St. völlig, oder sie sind nur an jüngeren Pflanzen vorhanden undfehlen an älteren Köpfen. Formen, welche Ar. von etwa 5 bis nahezu 10 mm Dm. haben und stärkere St., von denen der mittlere meist über 2 cm Länge hat und selten bis über 10 cm Länge erreichen kann, wird man als FORMA PERUVIANUS bezeichnen. Die Zahl der St. kannbei beiden Formen bis auf etwa 10 gehen, die Anordnung der St. und das Größenverhältnis zwischenRst. zuMst. ist bei beiden Formen dasselbe, Mst. sind nur einer vorhanden, seltener 2-3. Die St. beider Formen sind nur unterschieden durch Länge und Dicke; es mag also vielleicht für beide Formen nur je ein Allel eines einzigen Gen vorliegen, so daß eine Weiterführung des Namens PERUVIANUS als forma wohl nur aus Tradition zu rechtfertigen ist, wegen der Zweiteilung der Art durch Br. & R., denn solche Erbformen pflegt man an sich nicht taxonomisch zu benennen. Da eine genaue Bl.-Beschreibung nie erfolgte, gebe ich hier eine solche von einer Bl. (mit Foto) eines Exemplars östlich von SAMNE, Prov. OTUSCO, Depart. La Libertad, wo beide Formen mit Übergängen zusammen wachsen. Bl. seitlich, nicht sehr weit unter dem Triescheitel, ziemlich waagerecht vom Trieb abstehend, 21 cm lang, mit einer Weite zwischen den äußersten Krbl. vonca 20 cm. Über dem Frkn. ist die Rö. leicht nach oben gebogen, während die Öffnung der Rö. wieder leicht nach unten gebogenist. Frkn. 22 mm lang und dick, grün, gehöckert, mit schmalen grünen Schuppen von unten 1 mm bis oben ca 4 mm Länge und mit reichlichen schwarzbraunen Wollhaaren. N.-K. 23 mm lang, aber nur etwa 5 mm weit um den Gr., blaß bräunlich, mit etwas Nektar. Rö. darüber 8 cm lang, Öffnung 4,5 mm weit, mit 6 mm (unten) bis 25 mm (oben) langen graugrünen Schuppen und schwarzen, 15-25 mm langen Wollbüscheln. Stbf. blaßgrün, nach den Enden hellgelb, der Rö. aufliegend, 8-10 cm lang, die des Saumes 4,5 cm lang, Insertionslücke 4 cm lang unter dem Saum, Beutel brauncreme, 2,5 mm lang, 1 mm breit, Pollen weiß. Gr. blaßgrün, 19,5 cm lang, wovon 3 cm auf die 15 hellgelben, überragenden Narbenlappen kommen. Innere Krbl. weiß, 9-10 cm lang, 3,5-4 cm breit, bei etwa 2/3 Länge am breitesten, oben gerundet mit aufgesetzter hellgelber Spitze; äußere Krbl. 8-11 cm lang, 14-18 mm breit, fast von unten ab zugespitzt, nach unten hellgrün, nach den Enden rotbraun, stark nach außen gebogen. Einige Samenangaben siehe unter TRICHOCER. KNUTHIANUS. Nr. FR 567 (Form PACHANOI) und Nr. FR 155 (Form PERUVIANUS). Abb. 1186.
Videos of Trichocereus peruvianus / Echinopsis peruviana
This amazing Trichocereus Australia collection can be found in a private garden in Australia. We were given the chance to show this beautiful collection here on our site and I am proud to have it. All photos: Simon Maddern
Trichocereus macrogonus, also known as Echinopsis macrogona, is a columnar cactus.
The first description about it was made using the name Cereusmacrogonus SD. Cact. Hort. Dyck.Cult.
Currently valid name name:
Echinopsis macrogona, the name is disputed by some authors and re-described as Trichocereus macrogonus by others. The whole genus Trichocereus is currently being revised and it´ll take a good 10 years till this is somewhat resolved. Echinopsis macrogona / Trichocereus macrogonus is at least partially synonymous with Echinopsis peruviana / Trichocereus peruvianus and it is difficult to clearly divide them. Both are contending names and due the older age of Trichocereus macrogonus (back then it was still called Cereus macrogonus, which was the name from the first description by Salm-Dyck), it´s possible that Trichocereus macrogonus / Echinopsis macrogona will replace Trichocereus peruvianus / Echinopsis peruviana as main species name for this group of plants.
T.macrogonus and its connection to Trichocereus peruvianus
Trichocereus macrogonus is an alternative name for some forms of Trichocereus peruvianus and many authors support this theory. These days, some Peruvian Trichocereus strains with brown spines and dark blue epidermis are usually sold as Trichocereus macrogonus by seed sellers, but these plants are not really different enough to justify treating them as correct species.
Trichocereus macrogonus is a very old name and since Britton and Rose came along with their description of Trichocereus peruvianus, the plants that used to be called Macrogonus were then treated as T. peruvianus. Due to the old age of the species name Trichocereus macrogonus, it is possible that it will be given priority over the newer name T. peruvianus IF the original description of T. macrogonus will be considered to be correct. Right now, this hasn’t been decided yet, but there’s a chance that this will happen. However, many people want to keep the old name Trichocereus peruvianus just because it has a lot of history and traditions attached to it. The future of this species s is unclear and will be decided in the next years. Personally, I consider the name to be extremely problematic due to the many problems associated with it, eg no type locality, no flower description, unclear origin, not being found again in nature, etc.
Synonyms of T. macrogonus:
Cereus macrogona, Echinopsis macrogona, Trichocereus macrogona, Trichocereus glaucus (sometimes. Trichocereus glaucus is a species related to T. chalaensis. However, many seed sellers offer certain strains from the T. peruvianus/macrogonus group as Trichocereus glaucus, eg KK336). Echinopsis glauca, Trichocereus glauca, many strains that belong to T. peruvianus.
Below you can find some photos of plants with this name from the commercial market. They differ greatly and not all belong to Trichocereus peruvianus. There are plants with the label Trichocereus macrogonus being sold that belong to T. bridgesii, T. pachanoi, T. peruvianus, T. werdermannianus, T. taquimbalensis, T. tacaquirensis, T. santaensis, T. bridgesii and Trichocereus cuzcoensis. Because of this, it makes no sense to use plants from the commercial market as standard for this species.
European Macrogonus clone. Very old clone and one of the oldest ones associated with the name.
Different clone that was sold as Trichocereus macrogonus
European Trichocereus macrogonus clone
The photos below show Trichocereus macrogonus in the Huntington Botanical Garden
Trichocereus macrogonus in the Huntington Botanical Garden by Richard Hipp
Origin of Trichocereus macrogonus:
Unkown. Possibly Bolivia but the species could never be found in Bolivia again. Originally, it was assumed that the plant came from Brasil and Borg wrote that the plant came from Bolivia or Argentinia but that could not be verified. Rauh found a Trichocereus in 1954 (collection number K68-1954) that may have been the wild Trichocereus macrogonus. That plant was found around the Mantaro Area in the middle of Peru.
This is the plant in question, and judging by its looks, it could actually be the originally described Trichocereus macrogonus. Back then, the plant was described as Cereus macrogonus (Salm-Dyk) and I know a very similar plant that was distributed by Karel Knize.
Backeberg´s and Rauh´s Photos
And this pic is from Backeberg´s description and shows a plant that is very common in European collections!
Echinopsis macrogona or T. macrogonus is a columnar cactus that is very close to Trichocereus peruvianus or Echinopsis peruviana. Echinopsis macrogona is most likely synonymous with a certain, long-spined type of Peruvianus. The typical epidermis of Trichocereus macrogonus has a frosty, blue color. Trichocereus macrogonus grows columnar and can get up to 3 meters tall and 3-5 centimeters in diameter. Some very large species can even reach a higher diameter. It has 6-9 radial thorns and 1-3 middle thorns that are up to 10 centimeters long.
Spines of Echinopsis macrogona:
The spines are dark brown, black or gray in color. New spine growth can also be yellow. The problem is that there are countless types that are called “Trichocereus Macrogonus”. Some definitely belong in the Trichocereus Cuzcoensis complex while some others are a very frosty type of Trichocereus Peruvianus from Matucana.
About 2 centimeters apart from each other and 5-10 mm in diameter. Brown-felted.
Flowers:White, near the top and up to 18 centimeters long. Trichocereus Macrogonus is a night flowering species.
Fruit: Round fruit, shiny segmented fruit, black or dark brown in color.
Trichocereus Macrogonus is self sterilewhat means that you need two different species´to get seed.
Culture of Trichocereus macrogonus:
The culture of Trichocereus Macrogonus is very easy. Basically, it has exactly the same requirements as Trichocereus Pachanoi (San Pedro Cactus) or Trichocereus Peruvianus (Peruvian Torch). It is a very hardy plant that forgives a lot and as long as you treat it like a cactus instead of a swamp plant, it will pay you back with healthy growth every year. The cactus only needs water during the hot, growing seasons. That means that in summer, you can water it every week or even days as long you allow the soil to dry up between waterings.
You can improve the drainage o
The importance of providing drainage
f your soil by adding purely mineral substrates like pumice, clay substrates like Seramis or simply sand. However, you should add a very small part commercial cactus soil because you want the substrate to be able to store nutrients and purely mineral substrates like sand tend to wash out nutrients very easily. Trichocereus Macrogonus likes a place with half-shade that gets a fair amount of sunlight every day. However, you should make sure not to burn the hell out of it. You need to adapt your plants slowly to sun light and if necessary you need to provide a shade cloth.
Winter & Frost: Trichocereus Macrogonus is a very hardy cactus that can take short night frosts down to -9° Celsius as long as the general health of the plant is ok. However, it requires a minimum average temperature of 10° celsius. That means it can take short frosts down to 15.8° Fahrenheit as maximum frost temperature. The average minimum temperature in Fahrenheit is 50° Fahrenheit.
Winter storage & Winter Protection:
Trichocereus Macrogonus likes a bright spot with lots of fresh air during the wintertime. If you have the luck to live in a country with very little frost, like Australia or the hotter parts of the USA, you wont have the problem of winter storage because you can grow your plants outside but most people in other parts of the world are not able do that.
Fresh air to tackle fungal problems
It´s best to store cacti in a very bright room with fresh air supply to prevent mold. The minimum temperature should be around 9° celsius/50° Fahrenheit. For this type of winter storage, the plants need to be kept dry, without any waterings in between October and April. If you have a greenhouse, you can start taking out the plants by May, but be careful about late night frosts because some south american species that take frost very well. For Trichocereus Macrogonus, this should not be a problem though.
Germination of Trichocereus macrogonus seeds:
The seeds of Trichocereus Macrogonus are like most other Echinopsis & Trichocereus seeds. They need light to germinate and should be sprinkled on top of the soil. They require a minimum germination temperature between 25° and 30° celsius and seedlings need to be watched carefully to prevent heat damage, because though temps up to 30° celsius increase germination rates, everything above can kill the young seedlings in an instant. Watch out for mold or fungus gnats. However, Trichocereus Macrogonus seedlings are actually tough.
Where to get seed:
There are many seed suppliers that sell seed of Trichocereus macrogonus. However, be cautious because there one or two south american wholesalers that sell over aged seed. Please not that there are some extraordinarily good Seed distributors from South America so there is no general rule of thumb. That´s how life is and I would recommend you to test the seed you are offered before you buy a substantial amount of it. I have seen people tank hundreds of dollars for seed that produced one or two seedlings.
Seed Viability, Trichocereus macrogonus:
The seed is viable for many years. This is something that most Trichocereus have in common and the seed is probably viable for at least 5-10 years, though you get the best results within the first year.
Commercial strains, clones or field numbers associated with the name:
KK923 Trichocereus Macrogonus (Cieneguillas, Bolivia), KK1422 (Villa Abecia, Bolivia), KK2151 (Ayacucho, Peru), KK2175 Apurimac Pachachaca (Bolivia), KK2176 Ayacucho, Tr. macrogonus H1306 from the Huntington Botanical Garden, Trichocereus cv. Neon Palm, Trichocereus sp. Luther Burbank, Trichocereus SS01, Trichocereus cv. Oklahoma, and many more. List will be updated. If you know some more, let me know. But the fact that you could as well list all of those as Trichocereus Peruvianus makes this kinda pointless. Both types are synonymous and I just added this page because I dont want to leave it out.
Trichocereus macrogonus for sale
Trichocereus macrogonus is rarely available for sale. The species name is very old and the plants on the commercial market that you get with this label belong to all kinds of species. Most Trichocereus macrogonus for sale are Knize sourced Trichocereus werdermannianus, Trichocereus peruvianus, Trichocereus bridgesii etc.
Trichocereus macrogonus seeds
This is a completely informational page and we do not sell seeds or plants of this species. Like mentioned before, you can get Trichocereus macrogonus seeds from the commercial market. Since it is not known how the original Cereus macrogonus looked like, you can get all kinds of plants under this name though. Trichocereus macrogonus and Trichocereus peruvianus are at least partially synonymous and sellers use both names interchangeably.
This here is what grows out of Köhres or Knize Trichocereus Macrogonus Seed:
Trichocereus macrogonus ‘Fields’
The Fields Macrogonus is an old Australian Trichocereus macrogonus clone that came to Australia through Blossfeld´s first South America expedition. Harry Blossfeld was a cactus collector that financed his expeditions by selling cacti to financiers, and that´s how it probably was with the Fields Macro.
European Macrogonus Clone
Different phenotype, associated with Trichocereus macrogonus.
Red or brown spines are an important way to differentiate between them.
Aerial roots of Trichocereus macrogonus
Good example of a Bolivian Trichocereus macrogonus sourced from Karel Knize. The plant is almost certainly a relative of Trichocereus werdermannianus or taquimbalensis.
Trichocereus macrogonus / Echinopsis macrogona ‘MG Red Spine’ (Rodni Kisar)
European Macro clone
Wild populations from Matucana that may or may not count as Echinopsis macrogona.
Videos on how to differentiate between certain T. peruvianus and T.pachanoi
The Trichocereus peruvianus clones Rosei 1 & Rosei 2 are among the most interesting Trichocereus cultivars out there. Both are very glaucous with a dark blue skin. They have yellow or dark brown spines that often have black tips. The old spine growth looks very gray and the areoles are covered with very fine, white wool.
Trichocereus ‘Rosei 2’ was part of the legendary Australian Fields collection. Both Trichocereus rosei clones were brought to Australia by Harry Blossfeld, who was one of the first importers of cacti. . Prier donated some pics of the original mother plant at Fields and I am extremely glad we have them on the site.
“Rosei2” is certainly not a real species name and belongs into the context of Trichocereus peruvianus / Echinopsis peruviana. It is very similar to the dark blue Trichocereus peruvianus plants coming from Matucana and it´s possible that it was originally collected there. Either as seeds or as a live cutting. The spine color can be very variable and this clone is known to produce massive spines, which can be seen on some of the photos.
ICARO DNA is a strain of Trichocereus macrogonus/peruvianus from Peru. They are collected by the reputable vendor Julio from the Icaro DNA shop, who has been active for many years now.
Their strain is an extremely blue and spiny Peruvianus strain that comes from the Matucana region on Peru. Everyone who ever grew some of them knows that they are THE epitome of a non-cuzco Peruvianus. The shop owner Julio & his ICARO DNA shop have been around forever and just earned a reputation for their consistently great quality.
The ICARO seeds were picked up by many shops and ended up being one of the more common strains around Australia and other parts of the world. Those plants are not clones, but grown from Matucana seeds which are genetically diverse.
Here are some pics for your viewing pleasure! The Photos were donated by Trichocereus.com.au, SAB member Getafix, Blowng,Naja Naja & Sebastian Preiss! If you want to see some more photos of Icaro DNA, check out our Trichocereus Facebook group: https://facebook.com/groups/trichocereus
Also check out the general description page of this species here:
Chavín de Huántar: Trichocereus santaensis & El Lanzon
Chavín de Huántar is an archaeological site in Peru with a long history of Trichocereus cultivation. There are plants that can be found within the ruins and those plants probably go back for many thousands of years. The ruins are thought to be from 1200BC and the age of this complex is energetically discussed among archaeologists.
This legendary place is located in the Ancash area and holds great religious as well as historic significance, which is why the center was in the midst of the Chavin culture. It is located near the important Peruvian city Lima and lies at the confluence of two large rivers: The Rio Mosnar and the Huanchecsa river. The Trichocereus strains from this area have a huge botanic variability and the area is home to a large number of different plants and Trichocereus species.
The regional form known from this area is probably somewhere between Trichocereus cuzcoensis and Trichocereus peruvianus. We saw plants that clearly belonged into the Trichocereus santaensis group as well as other weird plants…some of which even look like Trichocereus huanucoensis.
BK09509.2 Trichocereus sp, Chavin, Ancash, Peru
Another great Specimen from the Ancash Region in Peru.
BK09508.2 Trichocereus sp, Chavin, Ancash, Peru 2009
BK09509.1 Trichocereus sp, Chavin, Ancash, Peru
BK09509.1 Trichocereus sp, Chavin, Ancash, Peru 2009
El Lanzon Trichocereus :
This legendary photo is made by Aplantis.net:
This plant has a great history and most people who visit the area can´t go by without taking loads of photos. It´s one of my most favorite plants.
Those plants were posted by ChavinHerbalist. They are trying to preserve the genetics and posted some amazing photos on Facebook. Check them out!
Photos below Trichocereus santaensis / Echinopsis santaensis in Chavin de Huantar, El Lanzon (Riley Flatten)
Trichocereus macrogonus ‘Fields’, also known as Fields Macrogonus is a Trichocereus that was originally part of the legendary Fields collection in Australia. The collection was founded in the early days of cactus collecting. Most of the plants from Fields, including the Fields Macro, were brought to Australia through Harry Blossfeld´s South America expedition. This was long before all the import restrictions on plants and cacti were put in place. The garden is now owned by Robert Fields, who took over the garden from his father, the person who began with the collection.
Now back to the history of the Fields Macro. Harry Blossfeld, who was a field botanist, offered some cactus shares to finance his 1935 South America Expedition and Mr. Field was one of the people who took the chance to invest in it. In return, he received some very cool cacti that grew in what is known as the “Field´s Collection”. In addition, Mr. Field seems to have bought some plants or seeds from Friedrich Ritter, because some of their plants were (at least officially) discovered by Ritter, such as Trichocereus knuthianus.
This Fields Macro, also known as Trichocereus macrogonus ‘Fields’, is one of the oldest confirmed specimens of Trichocereus macrogonus that are labeled as such. Of course there are still plants around from the early days of cactus taxonomy, but the majority of them have lost their labels.
At the time of the expeditions, Britton and Rose had just described their Trichocereus species Trichocereus pachanoi, Trichocereus bridgesii and Trichocereus peruvianus and Trichocereus macrogonus was still a very well known species, even more well-known than Trichocereus peruvianus.
There are a lot of plants labeled Trichocereus macrogonus on the market today, but the great confusion surrounding the name makes it very hard to differentiate between the ones that were originally called Trichocereus macrogonus and the ones that modern nurseries or seed collectors just identified themselves. On the commercial seed market, you can get all kinds of different species under the name Trichocereus macrogonus and plants from the commercial market are generally unfit to be used as standard for Trichocereus macrogonus.
Most Trichocereus macrogonus strains from Peru usually fall into the species Trichocereus peruvianus, which is why I think both names are at least partially synonymous.
In addition, the original description of T.macrogonus was very incomplete. There is no country of origin, no good photos from the earliest examples of Cereus macrogonus, no Herbarium specimen, no early flower description etc.
From the time when Britton and Rose described T. peruvianus, the original Trichocereus macrogonus was never found again and today no one really knows which plant was originally described in the description. And because of that, an early example of Trichocereus macrogonus that goes back to the 1930s is a great thing! If you are interested in the history of Trichocereus Macrogonus, check out my article here:
Personally, I think the Fields Macrogonus looks very much like a Matucana Peruvianus such as Icaro DNA or Los Gentiles. This particular form of Trichocereus peruvianus has brown spines and is very close to the overall description of Cereus peruvianus.
The Los Gentiles strain is mostly known through the California based Nursery Sacred Succulents, who has been offering crosses with this type for years. They sell both seeds and cloned plants, which is why there is a large generic diversity.
LOS GENTILES is Trichocereus peruvianus / Trichocereus macrogonus strain with a frosty epidermis and the color of the spines varies between Gold and reddish brown. Most of the spines have black tips and the ribs indicate that it is closer to Trichocereus peruvianus than it is to other strains. It definitely is an interesting population and I will add further info about it later on.
It is very similar to Trichocereus peruvianus strains from the area to the area around Matucana. Outside the United States, this clone is rare. There are a few local populations that look very much like it.LOS GENTILES is NOT the same strain as Trichocereus peruvianus ‘Icaro DNA’, but these two strains are so similar that I am very positive that they come from the same area in Peru. Sacred Succulents are the only source for this type of Trichocereus apart from the people who bought them there and sold or traded them. Trichocereus ‘LOS GENTILES’ is an extremely fascinating population. And even if that´s not the case, it still is a fantastic Trichocereus with a deep blue epidermis and strong spines that have written “Dangerous” all over them.
In my personal opinion, LOS GENTILES is the same population as ICARO DNA.
Both Rosei 1 and Rosei 2 are among the most popular clones in the Trichocereus community. Just like so many great plants, they originated from the Fields collection in Victoria. The name was used in very old cactus literature to label a certain, very blue types of Trichocereus peruvianus / Echinopsis peruviana. This name was mostly applied to the same plants that we label as Trichocereus macrogonus today. The name is mostly synonymous with certain forms of Trichocereus peruvianus.
The name Trichocereus rosei was never an officially described species and that´s why we count both Rosei clones as commercial varieties. Both clones are part of the Fields collection and came to Australia in the early days of cactus trading. Mr. Fields was one of the supporters of Harry Blossfeld´s South America expedition and got the plants as reward for the support.
Despite the fact that Rosei 1 and Rosei 2 are actually clones, you can find very similar specimens in nature. In particular, we see a striking resemblance to the forms of Trichocereus peruvianus from Matucana (e.g. the Icaro DNA strain, Sharxx Blue etc). However, there are also similar plants in other parts of Peru and we probably won’t be able to find out where exactly they came from. In the future, I will have a look at old cactus catalogs to see if there might be some old seed lists that include the collection sites. The only information that is certain is that both clones are from South America, but that´s a pretty big area.
Rosei 1 has shorter spines than Rosei 2 and usually has a more glaucous/blue epidermis. But because the environment can have a huge influence on the look of a plant, I doubt that this works reliably.