To know how to cultivate our plants, we first need to find out as much as possible about the habitat conditions in which they grow. Having this information will give us some idea of the kind of conditions we must try to provide to keep the plants healthy.
The main factors we need to take into account are:
When we have learned about these factors, we will be able to apply this knowledge to the requirements of cultivation:
Members of the genus Notocactus are found in the Southern Brazilian states of Parana, Santa Catarina and Rio Grande do Sul, Paraguay, Uruguay and the Argentinian states of Misiones, Corrientes, Entre Rios, Buenos Aires, Cordoba, Mendoza, Rio Negro, Catamarca and San Luis. The main concentration of Notocactus can be found around the border between Rio Grande do Sul and Uruguay. Paraguay contains only members of the subgenus Eriocactus and the ubiquitous N. ottonis. While in Argentina only members of the subgenera Eriocactus and Malacocarpus (Malacocarpus), together with N. ottonis and submammulosus are found. The species with the largest distribution is N. ottonis (and its varieties and forms), which may be found over the whole range for the genus.
There is also the unique Notocactus (Malacocarpus) vorwerkianus. This plant is very interesting because of the fact that it was discovered growing near Sagomosa, north of Bogota, Columbia. A distance of at least 3000 Km from the normal distribution of the Notocacti. It appears to be very closely related to N. (Malacocarpus) sessiliflorus and was almost certainly transported to Columbia via Humans or Birds.
The Brazilian states of Parana, Santa Catarina and the northern half of Rio Grande do Sul are at altitudes of between 500 - 1500m above sea level. As we move south through Southern Rio Grande do Sul, Uruguay and into Argentina the altitudes drop towards sea level. Notocacti grow at relatively low altitudes, below about 1000 m, in areas that receive quite a high annual rainfall (80 to 130 cm in Uruguay and 120 to 200 cm in Brazil) compared with other cacti and succulent plants.
Species of Notocactus can be found growing together with species of Frailea, Gymnocalycium, Echinopsis, Cereus and Opuntia.
The types of soil the plants are found in are obviously a major factor that we must take into account. The soil characteristics we need to look at include the composition of the soil, with regard the relative amounts of organic and inorganic components, drainage characteristics and pH.
Notocacti are found in a wide variety of habitats, ranging from mountains up to about 1000m in altitude to flat grasslands. However they are found mostly on "islands" of low rocky hills found in grasslands and forests, growing between cracks in the rocks or in the shade of larger growing plants. The soil here is well drained and has a fairly high organic content, derived from the decomposition of other plants. Due to the well drained soil, species of Notocactus are able to stand winter conditions of temperatures down to 8°C and below, together with considerable amounts of rain. In fact many of the plants found in the Brazilian states of Parana, Santa Catarina and the area north of Porto Alegre, RGdS, can be found growing in moss. These plants include members of the subgenus Brasiliparodia e.g., rechensis, alacriportanus, brevihamatus etc. The high organic content results in a soil which has an acidic pH (between 4.0 and 6.0).
The other major influences on our plants are the rainfall and temperature variations. Shown below are a series of graphs showing these variations for a number of the localities where species of Notocactus can be found growing. These give us some indication of why some plants need a slightly different treatment than others. I have only included a small number of graphs to show a few of the major areas of Notocactus distribution.
It is not essential to study these graphs, they are only included for reference. If you feel your brain turning to mush, just skip over them.
All of the graphs include the average monthly rainfall in blue and the temperatures in red. With the exception of the first graph, the range of the axes are identical to allow easier comparison of localities. Please note that the temperatures are only monthly averages and do not give the most accurate picture. Summer temperatures can reach 36°C and winters nights can go below -10°C, with the plants occasionally being covered by snow for short periods.
|Kew Gardens, London, England. 51.50°N, 0.30°W 5m|
|Annual Rainfall||615mm||Average Temperature||10.4°C|
OK, we start with my "home", London, England. Here in the Northern
hemisphere we have our winters between the months of October and March and the
summer is somewhere in between, with June - August being the warmest months.
Here in England, as can be seen, the hottest periods are also our wettest. The
winters can reach a low of -16°C and and the summer a high of about
Please note that the range of the temperature scale has been extended, relative to the following graphs, so that the low winter temperatures encountered here in London are visible.
|Curitiba, Parana, Brazil. 25.43°S, 49.20°W, 949m|
|Annual Rainfall||1415mm||Average Temperature||16.5°C|
Curitiba is at the northern most extent of the distribution of Notocactus.
It is here that we find various plants related to N. ottonis such as
carambeiensis and its variety villa-velhensis, and forms of
The most obvious difference to the previous graph is the red temperature line has been inverted. This is because these localities are in the southern hemisphere. In this, and all subsequent graphs, the highest temperatures are found at the beginning and end of the year. And the "colder" periods are in the middle. Luckily for us the plants don't care where they grow, as they can can tell the seasons no matter where they are growing.
Also very obvious are the amounts of monthly rainfall are much higher then in London. The largest rainfall corresponds with the higher temperatures, but there is still relatively high amounts of rainfall even in the winter periods. It is this fact that is important to remember when growing Notocactus in captivity.
|Porto Alegre, Rio Grande do Sul, Brazil. 30.02°S, 51.20°W, 47m|
|Annual Rainfall||1333mm||Average Temperature||19.4°C|
Porto Alegre and the area north of it, are where we find all of the members of
the subgenera Brasilicactus eg.
graessneri and haselbergii and
rechensis, alacriportanus, brevihamatus etc, some
Eriocactus eg, leninghausii and
warasii, and various taxa related to ottonis. The members of
Brasiliparodia are nearly always found growing together with moss and
lichen. Whilst Brasilicactus are found growing in moist rocky crevices.|
The temperature variation in this graph is practically identical to the previous example, as are most of those that follow. During the winter night time temperatures can go as low as -10°C and these plants can be covered in snow! But as soon as the sun comes out the temperatures pick up and melts the snow. Of most interest to us is the fact that this area gets the largest amounts of rainfall in the winter periods. The fact that both Brasilicactus and Brasiliparodia are only found in this area shows that their growing requirements are quite specific.
|Alegrete, Rio Grande do Sul, Brazil. 29.68°S, 55.50°W, 92m|
|Annual Rainfall||1656mm||Average Temperature||19.0°C|
In the area surrounding Alegrete we can find species belonging to subgenera
Malacocarpus, Notocactus eg forms of
ottonis and related taxa, Neonotocactus eg. forms of
mammulosus etc, and Eriocactus magnificus.|
The temperature line is as before. The amounts of rainfall are fairly high with a noticeable reduction corresponding to the lower winter temperatures.
|Rivera, Uruguay. 30.88°S, 55.50°W, 242m|
|Annual Rainfall||1622mm||Average Temperature||18.0°C|
Rivera is near the border of Rio Grande do Sul and Uruguay and is located on
the mountains of the Cuchilla Negra. Here we find members of the subgenera
Malacocarpus eg. sellowii, Neonotocactus eg. orthacanthus,
forms of mammulosus and mueller-melchersii and Notocactus
eg. herteri, minimus and forms of ottonis.|
Temperature line is as before. The most noticeable features of the rainfall are the slight reduction during the coldest period, but even here it is still relatively high. And as the warmer temperatures appear there is a large increase in the amount of rainfall. There is also a smaller, but still pronounced, increase as the temperature drops.
|Paysandu, Uruguay. 32.33°S, 58.00°W, 61m|
|Annual Rainfall||1193mm||Average Temperature||17.9°C|
Paysandu is on the border between Uruguay and the Argentinian state of Entre
Rios close to the river Uruguay. Growing here are members of the subgenera
Malacocarpus eg. sellowii and Notocactus eg. forms of
Again the temperature line is practically the same as before except that the min-max range is slightly extended. The rainfall line is similar to that of Rivera. Again there are the two rainfall peaks, the first as the temperatures begin to drop and the second as they begin to increase again. There is also the reduction in rainfall during the colder periods, but this is a far larger drop than before. Also quite noticeable is the drop in rainfall during the hottest months.
|Treinta-Y-Tres, Uruguay. 33.22°S, 54.30°W, 46m|
|Annual Rainfall||1259mm||Average Temperature||16.9°C|
Treinta-Y-Tres is located in the central eastern part of Uruguay. Growing here
we can find species belonging to subgenera Malacocarpus eg.
sellowii, its variety turbinatus and pseudopulvinatus,
Notocactus eg. forms of ottonis and scopa var.
marchesii and Neonotocactus eg. mammulosus.|
Again the temperature line is the same. However the rainfall line is almost a mirror image of the previous two Uruguayan localities. Here the wettest periods are also the warmest and there is also an increase in rainfall during the coldest months.
|Punta Del Este, Maldonado, Uruguay. 34.97°S, 54.90°W, 16m|
|Annual Rainfall||1037mm||Average Temperature||16.5°C|
We now come to the last of the localities from Uruguay that I'll be dealing
with. This is Punta Del Este, in the state of Maldonado, which is on the
Atlantic coast. Growing here we find members of the subgenera Malacocarpus
eg. neoarechavaletae and erinaceus and Notocactus eg.
scopa, tabularis, concinnus.|
Because of its proximity to the Atlantic coast you will notice the maximum temperatures are not as high as the other localities and also the coldest periods last longer. The rainfall is highest towards the end of the warmer period. We have another peak as the temperatures start to rise and then a very sudden reduction.
|Villarrica, Paraguay. 25.75°S, 56.40°W, 189m|
|Annual Rainfall||1575mm||Average Temperature||22.1°C|
We now come to the the Paraguayan locality of Villarrica, where we find variants
of ottonis var. paraguayensis and members of the subgenus
Eriocactus eg. ampliocostatus and grossei var.
Here there is a marked increase in the minimum and maximum temperatures. The rainfall is heaviest during the warmer periods and lowest during the periods of cooler temperatures.
|Cordoba, Argentina. 31.40°S, 64.20°W, 425m|
|Annual Rainfall||718mm||Average Temperature||17.3°C|
The last of the localities I have included is Cordoba, which is situated in the
Sierra de Cordoba, Argentina. This is the western most edge of Notocactus
distribution. Here we find only variants of Malacocarpus sessiliflorus and
Here the rainfall and temperature lines are almost identical in profile, with hot, wet summers and cooler, dry winters.
So what have we learned from wading through all of these graphs ? Hopefully it is obvious that there are some factors that are fairly consistent over much of their area of distribution.
There are also localities where conditions are obviously different to others. Most noticeable of these are the higher altitude localities at the northern extent of the distribution of Notocactus, eg. Porto Alegre. Around this area we find the entire distribution of the subgenera Brasilicactus and Brasiliparodia. When we consider the large distribution area of the genus Notocactus, there must be something "different" in the requirements of these two subgenera that prevents them from achieving a distribution as large as the other subgenera, such as Malacocarpus etc.
Therefore, if we know the conditions in which a particular taxa, i.e. subgenus, group of species or single species, comes from we are better able to make some informed decisions on how best to treat them.
Like other cacti, species of Notocactus have developed means of reducing water loss. They have a thick waterproof cuticle that keeps water in and tries to keep pests and diseases out. Cacti have also recessed their stomata in deep pits over their bodies. (Stomata are pores in the epidermis of plants that allow the plants to "breath", they also allow water to escape when they are open.) By recessing these pores in pits, the amount of water that is lost is drastically reduced. Cacti, along with many other plant groups found in arid conditions, also only open these pores during the night, when the temperatures are much lower, thus reducing water loss even further.
Those plants that are generally found in full sun will tend to develop a larger coverage of spination than those that tend to be found growing under other plants. The only plants that are really prone to sun burning are the Paucispini, i.e. the plants related to N. ottonis.
Compared with the cactus genera of more arid areas such as Mexico, Chile etc, Notocactus species generally receive quite large amounts of water. For this reason there is little need for the development of large tap roots as found in genera such as Ariocarpus, Turbinicarpus etc. In Notocactus we find the root system to be fine and quite extensive. The root system of Brasiliparodia, in particular, has adapted to its habitat conditions by producing long fibrous roots up to 50 cm long. These roots grow in the thin layer of humus under the moss in which they grow. We do find plants with some degree of tap root development, particularly in the subgenus Malacocarpus, but they are never as noticeable as in Turbinicarpus etc.
Another effect of the relatively large amounts of rainfall is the species can reach quite large sizes, compared with Turbinicarpus etc. This can be accomplished by prolific offsetting as in plants related to ottonis etc, or by producing large individual plants, as in subgenus Eriocactus where some specie reach well over a meter in height and plants related to herteri can reach 20 cm Ø. To be able to store this water, many species of Notocactus have deep ribs that allow the plants bodies to expand.
The information given above, provides details of the conditions the plants receive in habitat. What we need to do is try to simulate, as best we can, these conditions in our greenhouses, so that we can provide the best possible conditions for our plants. Unless you live in a climate that is the same as that encountered in habitat, at least some of the information must be adapted to fit in with the conditions that exist in captivity.
For most of us it is going to be impossible to provide optimum growing conditions for each and every plant, it would just take up too much time and bench space. What we need to do is divide up the plants into convenient groups that require the same or similar conditions.
Please note that I live in England, where winter starts in about October and ends about March. They are wet and can reach temperatures as low as - 16°C. The summers are not as wet and temperatures can reach highs of 32°C. The information and advice given below are only guidelines and lessons that I have learned over the past 15 years, or so, of growing these plants. You may want, or need, to adapt them to suit your own particular situation. All I can say is that they work for me......most of the time.
Notocactus should be grown in a well drained soil, containing reasonable amounts of organic matter. The soil must also have a low pH, i.e. acidic, which should be below 6.0. I use a soil mixture of two parts John Innes no. 2, one part of coarse grit and one of peat. This soil is a good starting point, but the pH will tend to climb, i.e. become more alkaline, especially if tap water is used instead of rain water. To counter this tendency we will need to use some form of acidification. This may be accomplished by using proprietary soil acidification products, such as those sold for use with Azaleas, Rhododendrons and other acid loving plants, or by adding small amounts of acids directly to the water. The last method requires special chemicals to test the pH or a pH meter to make sure the correct amount of acid has been added, so is usually not the best option for us.
I tend to use BEF type square pots for most of my plants. For the larger offsetting species I will use round plastic pots. It is best to use dwarf pots as Notocactus generally have a shallow root system. I advise not using clay pots as these tend to dry out too quickly and will cause damage to the fine root system
When potting plants I place some pieces of gravel (6mm Ø) in the bottom of the pots to prevent too much of the soil being washed away during watering. This is then covered with a layer of about 1cm of our soil mix and the plant held inside the pot at a level so that the "neck" of the plant is just below the rim of the pot. Soil is added and gently pressed around the plant, up to a level about 1cm below the "neck" and the pot is then top dressed with coarse grit, I use the same grit as in the soil mix. I then give the plant a light spraying with water, to remove any soil from the body.
Most of the plants can stand full sun, with perhaps only some of the plants related to N. ottonis requiring any form of shading. Keeping the plants in full sun will make them look healthier and will result in stronger and more colourful spination. Some members of subgenus Eriocactus tend to grow on slopes in their habitat and will naturally tilt the growing point towards the sun. This is a natural state and is generally not an indication of lack of sun.
This year (1999) I have placed all of the Paucispini, ie. plants related to ottonis, outside in full sun and they seem to do much better than inside the greenhouse. The only thing we need to do is provide some cover during periods of extended rainfall.
All of the species of Notocactus are able to withstand winter temperatures down to about 5°C, with the exception of N. magnificus which tends to form brown patches if allowed to go below 10°C. For this reason I bring this plant inside the house over the winter.
The supply of sufficient amounts of water to the plants is the most important factor in the successful cultivation of all species of Notocactus. As we have seen from the graphs, virtually all of the species of Notocactus receive quite considerable amounts of rainfall over the whole year. Unfortunately for us growers in colder climates this is what causes the cultivation problems we encounter. All Notocactus species must have water throughout the whole year, otherwise their roots will dry and die. Which will result in checks in the rate of growth or plant loss. What we have to do is give small amounts of water over the winter, during periods of warmer weather. As always with cacti it is very important that the plants do not stand in water, only sufficient water to prevent the roots from drying out completely should be given.
I usually give my plants a dose of half normal strength fertilizer, once in every three waterings. I try to alternate between two acidifying fertilizers Phostrogen and ICI Miracid. When ICI Miracid is used it can affect some plants by turning the wool in the areoles yellow. To prevent this from happening I always give the plants an additional spray with plain water.
The above advice is sufficient for the majority of the Notocactus species. There are, however, some plants that have specific requirements. The first group of plants that need particular care are those that come from the wet higher altitude localities at the northern extent of the distribution of Notocactus, eg. Porto Alegre, RGdS, Brazil. These are the two species of subgenus Brasilicactus eg. haselbergii and graessneri and all of the Brasiliparodia species eg. alacriportanus, brevihamatus, buenekeri, rechensis etc. Coming from Northern Uruguay, the members of the series Fricianae eg. minimus, minimus var. tenuicylindricus, ruoffii etc. also need the same requirements.
I find that these plants will loss their roots very easily if the soil is allowed to dry out for any period of time. I water them perhaps 2 or 3 times a week in the hottest summer periods and two or threes weeks during the winter, just to keep the soil slightly moist. If you get algae or moss growing in the pots, then you are giving enough water.
By giving these species large amounts of water we are also increasing the threat of root rot. For the solitary species of Brasilicactus we just have to keep our fingers crossed and hope for the best; I have never lost one because of rot, those I have lost have died because their roots dried up. For the freely offsetting species of the Fricianae and Brasiliparodia what I do every year is to remove and pot up a couple of the offsets, so that I have "backups". Keep two or three of these "backups" in your collection and the rest you can pass on to other collectors.
The other group of plants that need a bit more care are the Melchersianae eg. mueller-melchersii, rutilans, roseiflorus etc. Which come from Northern Uruguay. These are the plants I have had the most problems with. Their roots will dry out and die over the winter and then the body will slowly, over a couple of years, die and dry up from the base. Plants from this area tend to receive an increase in rainfall as the temperatures decline as winter approaches and another heavier increase as the summer begins. Even during the coldest period there is a noticeable increase. What I do to these species is give them a heavy watering just before winter begins at about the middle of October. Then about mid december early January I give them a reasonable amount of water. Hopefully this watering will coincide with a mild period, if not the plants are bought indoors for a week or so.
There are really only two pest that affect species of Notocactus. These are the red spider mite and mealy bug. Infections of both of these can be eradicated by any of the proprietary insecticides, I personally use Malathion. With a particularly heavy infection of root mealy bug there is strong chance of a subsequent mould growth, in the soil, on all of the dead mealy bugs. What I have done in the past is to give the plants a dose of fungicide about a week after the insecticide to prevent this mould affecting the plants.
The diseases that affect these plants are usually problems with the roots. This can be caused by over watering or alkali soil. If the roots have been lost then all of the dead or damaged root must be removed. If there is any fungal infection, indicated by a brown discoloration of the tissue, it must all be removed with the use of a sharp, sterile, knife. The damaged tissue must be allowed to callous, by leaving in a dry, airy place, until the tissue is completely dry. Re-rooting can be attempted by placing the plant in a pot of moist sterile soil, which is placed inside a sealed plastic bag, to prevent the soil drying out. New roots should start to appear after a couple of weeks.
If a plant becomes sun burned it is important to place it in a shady position and give it plenty of water until it recovers. If the green colouration does not start to return after about two weeks, remove the plant from the pot and check for root loss or root mealy bug.
Plants of the series Herterianae are particularly prone to producing a brown corky growth at the base of the plants. As long as these plants are given a combination of sufficient water and nutrients this unsightly condition will be certainly reduced, if not prevented.
Because of the cold moist winters we have in England, we can get a growth of black mould on any remaining fruits. For this reason I try to remove as many of the fruits as possible as they ripen. To do this all you need to do is grip the fruit at the top and gently waggle it up and down or left and right. If the fruit is fully ripened it will come away from the plant with ease. This is OK for all of the species apart from those in series Setacei and subgenera Malacocarpus. In the Setacei the fruits will ripen, but will still be strongly attached to the plant. If we try to remove them by force, there will be some damage done to the plant. In Malacocarpus the fruits do not start to ripen until February to march the year following flowering. For this reason it is important to keep a close watch on these species and give them a spray with a fungicide during the winter.
One annoying thing about Notocactus is that as a flower dies it will tend to stick to any remaining open flowers. To prevent this you can squeeze the petals of the dead flower together.
Notocacti are fairly easy to grow from seed, as long as a sterile soil is used and the young seedlings receive sufficient moisture and fresh air. My preferred method of seed raising involves sowing up to 50 seeds in a 2½" (6.5 cm) Ø pot containing John Innes soil. The seeds and soil are soaked well by placing the pot in a dish of water and waiting until the soil surface becomes damp. A label containing the appropriate information, eg. plant name, date, number of seeds etc, is placed in the pot and the whole lot is placed inside a sealed plastic bag. The pots are examined every week or so and additional water added to prevent the soil from drying out. The seedlings are only potted up into larger seed trays or individual pots once they reach about 1 cm Ø or they start to force each other out of the soil.
Those plants that offset may be propagated from these. If the offsets do not have any roots of their own, they should be placed on top of a pot of moist soil and sealed in a plastic bag, roots usually appear after a couple of weeks.
There are no species of Notocactus that require grafting.