Light
Full Sun
Requires full sun or bright, direct sunlight on south-facing windows.
Reference image Maihueniopsis wagenknechtii
Wagenknecht's Hill Cactus
Overview
Maihueniopsis wagenknechtii is a cushion-forming cactus species belonging to the family Cactaceae, highly adapted to extremely arid and windy mountain climates 1. It survives by forming dense, low-growing mounds.
Taxonomy and Naming
Belonging to the subfamily Opuntioideae, the genus Maihueniopsis comprises jointed-stem cacti. This specific species was named in honor of Rodolfo Wagenknecht, an eminent naturalist who explored the flora of Chile 2.
Distribution and Habitat
Native to Chile, particularly thriving in the Coquimbo region, this species populates arid rocky slopes, high-altitude steppes, and dry shrublands 1. It grows in coarse, mineral-rich soils devoid of significant organic matter.
Appearance
It forms dense, low-growing mats of green to grayish-green ovoid or subglobose segments. The areoles are armed with sharp central spines and micro-spines (glochids). Yellow, cup-shaped flowers appear at the tips of the segments during late spring and summer 2.
Culture and Cultivation
In cultivation, this species demands excellent air circulation, maximum sunlight, and highly porous soil. Avoid peat-heavy potting mixes. Water only when the soil is completely bone-dry during the active growing season 2.
Common Cultivation Mistakes
The most frequent cause of loss is winter watering combined with low temperatures. Wet soil during dormancy quickly rots the roots.
Bibliography
References
Watering
12-35 Days
Water only when the substrate is fully dry in summer. Suspend watering in winter.
Soil
Highly drained mineral cactus mix with pumice and coarse sand
Use a heavy mineral mix containing 70% pumice, gravel, and sand, and 30% peat.
Safety
Pet Friendly
Possesses small, irritating glochids and sharp spines. Handle with thick gloves.
Difficulty
Moderate
Very easy if winter dryness is maintained, but highly sensitive to overwatering.
Native Habitat
Chile
Endemic to the dry, high-altitude Andean slopes and rocky deserts of northern and central Chile, particularly Coquimbo, where it withstands cold winters and hot, dry summers.
Frequently Asked Questions
Can Maihueniopsis wagenknechtii be grown in pots?
Yes, it can easily be grown in pots in a high-mineral drainage mix and a wide, shallow pot placed on a sunny windowsill.
How often should it be watered in summer?
In summer when the weather is hot, water thoroughly about once every 10-15 days, only after making sure the soil has dried completely.
Should it be watered during winter?
No, watering should be completely suspended during the winter dormancy period to prevent root rot.
What soil mix does it prefer?
It prefers a gritty cactus mix consisting of 70% inorganic materials like pumice, lava rock, and coarse sand, and 30% peat.
Does it need direct sunlight?
Yes, this species requires intense direct sunlight. South or west-facing spots receiving at least 6 hours of direct sun daily are ideal.
How can I encourage it to bloom?
To promote blooming, it must experience a cold, dry winter dormancy period (5-10°C) followed by full sun exposure in summer.
What is its growth rate?
It is a very slow-growing species. Over the years, it slowly spreads horizontally to form dense, low cactus cushions.
Is it toxic to pets?
It does not contain toxic chemicals, but due to its painful micro-spines (glochids) and spines, it should be kept away from pets.
Is it cold hardy?
Provided the soil is kept absolutely dry, it can tolerate short periods of frost down to -10°C (14°F).
How is it propagated?
It is easily propagated by detaching stem segments in spring, letting them dry for a few days, and then rooting them in dry, sandy soil.