Beautiful species. The F. "alamosesis" has few wide ribs which are a dull blue-grey in colour. The areoles are round bigand  woolly with few but strong creamy-white to pale-brown spines.

Family: Cactaceae (Cactus Family)

Scientific name: Ferocactus pottsi var. alamosensis

Conservation status: Listed in CITES appendix 2.

The plants of F. pottsii var. alamosensis (At least those found in cultivation) are very different from those of F. alamosanus. But we are not sure about the correct classification of this two very different species.

Description:  The plant labelled F. pottsi var. alamosensis we observed in cultivation are easily tell apart from the similarly named Ferocactus pottsii alamosanus, may be the name "alamosensis" is merely a misspelling of "alamosanus", in spite of this error of orthography the two plant are really different and both worth of cultivation.

"alamosesis" has few wide ribs which are a dull blue-grey in colour. The areoles are round big woolly  largely spaced with few but strong creamy-white to pale-brownies spines. The stem is only partially covered by spines and similar to that of F. pottsii.

"alamosanus" has numerous pale green to green-bluish ribs, the areole are elongated with thin needle-like spines than cover almost completely the stem.

(Left) F. pottsii var. almosensis and  (right)

F. (pottsii var. ) alamosanus are easily tell apart.

F. pottsii var. almosensis

F. pottsii var. almosensis

Cultivation: They are summer-growing and pretty easy plants thought slow to start. They are suited for any rich, well drained soil  such us clay, pumice, lava grit, and only a little peat or leaf-mould. If potted, repot them preferably in the spring, if their roots become cramped.  Generally, they should be repotted every other year in order to provide fresh soil. However, this doesn't necessarily mean they'll need larger containers. Fill about a quarter of the pot with broken crocks, gravel, etc. to promote good drainage. After repotting, do not water for a week or more. Water regularly during the aestival growth cycle (this plant need plenty of water, but do not overwater and let their soil dry out between waterings), and also needs to be avoided wetting the body of this plant while it is in sunlight. A wet cactus in the sun light can cause sun burning which can lead to scares or even fungal infections and death, keep rather dry in winter. No water should ever be allowed to stand around the roots. Feed with a high potassium fertilizer in summer.
Exposure: Outside they need a bright exposure, full sun or half shade in summer if the location is exceedingly hot or bright, inside needs bright light, and some direct sun. It can tolerate moderate shade, and a plant that has been growing in shade should be slowly hardened off before placing it in full sun as the plant will be severely scorched if moved too suddenly from shade into sun.
Frost Tolerance: Light frost protection required for safe cultivation, but can tolerate sporadic light frost. This plants need a period of cool rest in winter to produce flowers abundantly.
Diseases and pests: Watch for infestations of mealybug, scale insects and spider mite.
Plant in good conditions will start to  bloom when reach the diameter of only 15-18 cm.

Propagation: Seeds are the only way of reproducing.