''Astrophytum ornatum'', the bishop's cap or monk's hood cactus, is a

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (). The term angiosperm is derived from the Ancient Greek, Greek words (; 'container, vessel') and (; 'seed'), meaning that the seeds are enclosed with ...

of the family

Cactaceae A cactus (: cacti, cactuses, or less commonly, cactus) is a member of the plant family Cactaceae (), a family of the order Caryophyllales comprising about 127 genera with some 1,750 known species. The word ''cactus'' derives, through Latin, ...

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

to the Central Plateau of

Mexico Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundar ...

. It is the largest and tallest species of ''

Astrophytum ''Astrophytum'' is a genus of six species of cacti, native to North America. These species are sometimes referred to as living rocks, though the term is also used for other genera, particularly '' Lithops'' (Aizoaceae). The generic name is de ...

''.

Description

Solitary and cylindrical in form, it may grow up to in height and in width on the Central Plateau. It develops numerous white woolly flakes for protection from the sun. It flowers throughout the summer, the flowers being 7 to 8 centimeters long in canary yellow.

Cultivation

It is a rugged plant resistant to

root rot Root rot is a condition in which anoxic conditions in the soil or potting media around the roots of a plant cause them to rot. This occurs due to excessive standing water around the roots.-Hydroponics Root Rot: What is It, How To Treat It, How ...

, and easy to grow in a well-drained soil. It is dark green when grown in filtered light or shade. An established plant is cold tolerant to . ''Astrophytum ornatum'' has gained the

Royal Horticultural Society The Royal Horticultural Society (RHS), founded in 1804 as the Horticultural Society of London, is the UK's leading gardening charity. The RHS promotes horticulture through its five gardens at Wisley (Surrey), Hyde Hall (Essex), Harlow Carr ...

Award of Garden Merit The Award of Garden Merit (AGM) is a long-established award for plants by the British Royal Horticultural Society (RHS). It is based on assessment of the plants' performance under UK growing conditions. It includes the full range of cultivated p ...

. File:Astrophytum ornatum 17.jpg, It usually has 8 ribs, often in spiral File:A ornatum flowering.jpg, Flowers File:Astrophytum ornatum seeds.jpg, Seeds File:Astrophytum ornatum 25.jpg, A one month old seedling File:Astrophytum ornatum 34.jpg, Astrophytum one year after sowing

References

External links

*
''Astrophytum ornatum'' on Astroweb

* Simon & Schuster's Guide to Cacti and Succulents, Pizzetti,
photos on www.AIAPS.org

"Star Cactus (Astrophytum ornatum)"

photos on www.cactiguide.com
{{Taxonbar, from=Q133127 ornatum Cacti of Mexico Endemic flora of Mexico Flora of Central Mexico Flora of Northeastern Mexico Garden plants of North America