PlantPeers
Back to Catalog
No image available
Cactaceae FAMILY Least Concern

Opuntia macrorhiza

Opuntia macrorhiza

Edibility
2/5
Medicinal
2/5

Safety & Hazards

The plant has numerous minutely barbed glochids - these are barbed spines that are usually small to minute and are very sharp and brittle. The glochids are very easily dislodged when the plant is touched and can penetrate the skin where, because of their barbs, they become stuck and are very difficult to see and remove. They can cause considerable irritation and discomfort[1, 2]. Opuntia species can contain quite high levels of oxalic acid, especially in older parts of the plant. Perfectly alright in small quantities, foods containing oxalic acid should not be eaten in large amounts since it can lock-up other nutrients in the food, especially calcium, thus causing mineral deficiencies. The oxalic acid content will be reduced if the plant is cooked. People with a tendency to rheumatism, arthritis, gout, kidney stones or hyperacidity should take especial caution if including this plant in their diet since it can aggravate their condition[3, 2].

Cultivation Details

HabitEvergreen Shrub
Growth—

Opuntia macrorhiza is a fairly cold tolerant plant, requiring an arid or semi-arid climate with hot summers. Requires a sandy or very well-drained soil[4]. Prefers a pH in the range 6 to 7.5[1]. Plants must be kept fairly dry in the winter but they like a reasonable supply of water in the growing season[1]. A position at the base of a south-facing wall or somewhere that can be protected from winter rain is best for this plant. Requires warmth and plenty of sun. Plants tolerate considerable neglect. This species is closely related to Opuntia humifusa[5].

Propagation

Seed - sow early spring in a very well-drained compost in a greenhouse. When they are large enough to handle, prick the seedlings out into individual pots and grow them on in the greenhouse for at least their first two winters. Plant them out into their permanent positions in late spring or early summer, after the last expected frosts. Give the plants some protection from winter wet. Make sure you have some reserve plants in case those outdoors do not overwinter. Cuttings of leaf pads at any time in the growing season. Remove a pad from the plant and then leave it in a dry sunny place for a couple of days to ensure that the base is thoroughly dry and has begun to callous. Pot up into a sandy compost. Very easy, rooting quickly. Cite as: Temperate Plants Database, Ken Fern. temperate.theferns.info. 2026-02-21. <temperate.theferns.info/plant/Opuntia+macrorhiza>

Pollinators

Bees, Insects

References

  1. [1]The New RHS Dictionary of Gardening. 1992. — Huxley. A. · MacMillan Press · 1992 · ISBN 0-333-47494-5 ↩︎Excellent and very comprehensive, though it contains a number of silly mistakes. Readable yet also very detailed.
  2. [2]A natural history of the Sonoran Desert — Phillips S.J. & Comus P.W. · University of California Press; Los Angeles, California · 2000 · ISBN 0-520-22029-3 ↩︎
  3. [3]Encyclopaedia of Herbs and their Uses. — Bown. D. · Dorling Kindersley, London. · 1995 · ISBN 0-7513-020-31 ↩︎A very well presented and informative book on herbs from around the globe. Plenty in it for both the casual reader and the serious student. Just one main quibble is the silly way of having two separate entries for each plant.
  4. [4]Wonder Crops. 1987. — Natural Food Institute, ↩︎Fascinating reading, this is an annual publication. Some reports do seem somewhat exaggerated though.
  5. [5]An Illustrated Flora of the Northern United States and Canada — Britton. N. L. Brown. A. · Dover Publications. New York. · 1970 · ISBN 0-486-22642-5 ↩︎Reprint of a 1913 Flora, but still a very useful book.
  6. [6]The Cactus Family — Anderson E.F. · Timber Press; Portland, Oregon · 2001 · ISBN 0-88192-498-9 ↩︎An excellent work, giving botanical descriptions of virtually all the cacti, together with their range (but not their habitats) and sometimes also a photo. it also contains a long chapter detailing the many uses of cacti and another on cultivation..
  7. [7]IUCN Red List of Threatened Species — http://www.iucnredlist.org/ ↩︎A list of plants under threat and facing possible extinction, usually with brief details of the threats and information on habitat.
  8. [8]Flora of the Great Plains. — McGregor. R. L. & Barkley. T. M. · University Press of Kansas. · 1986 · ISBN 070060295x ↩︎A useful source of habitats.
  9. [9]Native American Ethnobotany — Moerman. D. · Timber Press. Oregon. · 1998 · ISBN 0-88192-453-9 ↩︎Very comprehensive but terse guide to the native uses of plants. Excellent bibliography, fully referenced to each plant, giving a pathway to further information. Not for the casual reader.
  10. [10]Food Plants in the Americas: A Survey of the Domesticated, Cultivated, and Wild Plants Used for Human Food in North, — Kermath B.M.; Bennett B.C.' Pulsipher L.M. · 2014 ↩︎A pre-publication draft of an amazing, on-going work first started in 1985. It contains information on more than 3,900 taxa from the Americas - from Arctic regions to the Tropics
  11. [11]Edible Native Plants of the Rocky Mountains. — Harrington. H. D. · University of New Mexico Press · 1967 · ISBN 0-8623-0343-9 ↩︎A superb book. Very readable, it gives the results of the authors experiments with native edible plants.
  12. [12]Edible and Useful Wild Plants of the United States and Canada. — Saunders. C. F. · Dover Publications · 1976 · ISBN 0-486-23310-3 ↩︎Useful wild plants of America. A pocket guide.
  13. [13]Cornucopia - A Source Book of Edible Plants. — Facciola. S. · Kampong Publications · 1990 · ISBN 0-9628087-0-9 ↩︎Excellent. Contains a very wide range of conventional and unconventional food plants (including tropical) and where they can be obtained (mainly N. American nurseries but also research institutes and a lot of other nurseries from around the world.
  14. [14]Trees and Shrubs of Mexico — Standley P.C. · Smithsonian Institution; Washington · 1926 ↩︎Although dated, it contains a wealth of information on the trees and shrubs of Mexico, including many of their uses. It can be downloaded from the Internet.
  15. [15]Uses of Opuntia Species and the potential impact of Cactoblastis cactorum (Lepidoptera; Pyralidae) in Mexco — Vigueras A.L. & Portillo L. · 2001 ↩︎
  16. [16]Vegetable Gums and Resins. — Howes. F. N. · Faber · ISBN 81-88818-17-8 ↩︎A very good book dealing with the subject in a readable way.
  17. [17]Early Uses of Californian Plants. — Balls. E. K. · University of California Press · 1975 · ISBN 0-520-00072-2 ↩︎A nice readable book.
  18. [PFAF]Plants for a Future — pfaf.org ↩︎