Echinofossulocactus inermis ‘Sperm cactus’


No synonyms are recorded for this species name.


Echinofossulocactus inermis ‘Sperm cactus’ is a nursery variety and thus doesn’t exist in nature.


Echinofossulocactus inermis ‘Sperm Cactus’ is a small, globose or slightly elongated cacti, usually small-sized: it reaches maximum height and diameter of 10 centimeters. It is a rare nursery cultivar and its epithet ‘Sperm cactus’ is due to the unique pattern of its wavy, numerous stem ribs: with their enlarged top and the wavy elongated ‘tail’ they definitely look like sperm cells. Also because their “head” is adorned with a whitish tip of colour and it is slightly depressed, like a little navel, standing out even more and standing out so the bottom part looks even more like a tail. These wavy structures thickly adorn the entire stem, attached to each other: they look almost like a group of spermatozoa proceeding upward, towards the apex of the stem. The “heads” mentioned above are actually the areoles (scientifical name of the buds of cacti). Although, usually, these areoles don’t produce any spine. Only once in a while do some appear, white, pointed and about 1-1.5 centimeters long. The top of the stem of this cacti is usually adorned with a white hair. Sometimes, a tuft of orange sepal-like structures and white spines appear. Also because it is often found grafted onto other cacti with erect stems, it is rare for it to flower. Nevertherless, its odd shape and its tiny dimension, along with its cute globose shape, provide it still a highly decorative potential.


Cultivating and propagating Echinofossulocactus inermis ‘Sperm cactus’ is straightforward, as it is a small-sized, easy-to-care-for plant that blooms beautifully. Its compact nature makes it an ideal choice for potted plant enthusiasts, especially those who are just starting out in collecting succulents.
In terms of growth rate, this species is considered slow-growing. It thrives in a well-draining mineral-based potting mix, but it’s not overly particular about the type of soil it’s planted in. When it comes to repotting, it’s crucial to use a pot with good drainage. As the plant matures, it can reach a maximum size of about 20 centimeters. However, it’s worth noting that older plants can become susceptible to disease and may develop a weaker root system. At this stage, they have a tendency to experience sudden decline and eventual demise. As a precaution, once they reach a diameter of 10 centimeters, it’s recommended to proceed with repotting every 2 to 3 years. Additionally, consider exposing them to drier conditions or providing them with stronger sunlight.
Watering should be done regularly during the summer, ensuring that excess water is allowed to drain away rather than pooling in the pot (as excessive moisture can lead to rot, especially if the plant is overwatered). It’s important to allow the soil to dry out between waterings. In hot weather, more frequent watering may be necessary, especially when the plant is actively growing. Starting from late September, reduce watering to encourage a semi-dormant state. By October, transition into a winter watering routine. Be cautious, as leaving the soil excessively dry for too long can result in root loss, while keeping the plants consistently wet and cold can lead to the same outcome.
Feeding with a high potassium fertilizer in summer can boost the plant’s growth. However, if the compost is relatively fresh, feeding may not be necessary. Avoid feeding the plants from September onwards, as lush growth during the darker, colder months can be detrimental.
When in dormancy, Echinofossulocactus inermis ‘Sperm cactus’ exhibits impressive cold tolerance, enduring temperatures down to nearly -5°C or even lower. However, it becomes more sensitive to frost when left outdoors. During the summer months, it’s best to keep the plants outside, where temperatures can rise above 30°C without harm.
While these cacti thrive with ample light exposure to develop their characteristic spines, different clones may have varying degrees of tolerance to full sunshine. It’s advisable to provide some protection from intense sunlight during the hottest hours of summer. If kept in excessively dim conditions, they may become overly lush and greener, potentially leading to issues with rot due to overwatering.
Echinofossulocactus inermis ‘Sperm cactus’ is an excellent choice for container gardening, maintaining an appealing appearance while remaining compact. It also complements the aesthetics of a cold greenhouse or frame. Rot is generally not a significant concern with these cacti if they are watered and provided with proper ventilation. However, if these care practices are neglected, fungicides may offer limited assistance in mitigating any resulting issues.


The propagation of Echinofossulocactus inermis ‘Sperm Cactus’ is usually carried out through grafting on more tough, erect stemmed cacti, that provide a higher resistance to adversities.


The name ‘Sperm cactus’ is due to the odd fact that the stem of this cacti seems adorned with sperm cells!

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