Rock Outcrops | Observations and Thoughts for a Desert Rain Garden

Rock outcrops have inspired me for years.  Since I was recently out hiking in rock outcrops in the Juniper Flats Area with Friends of Juniper Flats, I thought I would take some photos and introduce the basic concept behind some projects that I am planning for my yard.

High Desert hikers who like to take a break from hot desert sun know that rock formations shade and insulate the ground beneath them.  Crawl into openings under large outcrops, and you can kick back in a naturally cooled “room”.

FOJF - Annual Meeting

Cooling Off in Big Rock Shelter


That shady coolness means that water and moisture will take longer to evaporate after storms.  Plants called Phreatophytes take advantage of water that collects below ground in spaces between rocks. As a result, Rock outcrops are an example  of natural “rain gardens“.  When surrounding vegetation is dry and crispy, plants within root’s reach of rock outcrops will be cool and lush.



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While planning future garden projects, I like to pay particular attention to rock outcrops, also called rock formations.  Whenever I visit an outcrop, questions form in my mind and potential landscaping projects start to emerge.

  • How can I mimic the cracks and crevices in my garden where stormwater and runoff  collect and be protected from evaporation?
  • What are affordable, preferably free, materials I can use to make artificial rock outcrops?
  • What plants would I want to grow in my “outcrops?”
  • Can I propagate these plants myself without the benefit of a greenhouse, shade house, or automated watering systems?
  • Can I purchase plants for my “outcrop” from local nurseries?

Of course, my motivation is entirely selfish.  Rock outcrops show us how lush, green plants such as native cherries can flourish in a desert during a major drought without an expensive irrigation water.


More Information

I have read and even studied some of these references.  Others are on my wish list. I couldn’t think of a better place to keep this list, and I thought you might find the links handy too.

A manual of California vegetation. 1995. Sawyer, J.O. and T.Keeler-Wolf.  The California Native Plant Society. Sacramento, Ca.

Appendix: the map of the natural vegetation of California. 1977.  Kuchler, A.W. In: The terrestrial vegetation of California. M.G. Barbour and J. Major (Eds.). New York: Wiley Publications.

CALVEG: Mosaic of existing vegetation of California. 1980. Matyas, W.J. and I. Parker.  Regional Ecology Group, U.S. Forest Service. Department of Agriculture. San Francisco, California.

Cougar ButtesWalter Feller. ex. Desert Gazette, Accessed on Sept. 25, 2016.

Desert communities: an overview of patterns and processes. Polis, G.A. 1991. Pages 1-26 in G.A. Polis, editor. The ecology of desert communities. University of Arizona Press, Tucson, Arizona, USA.

Development of vegetation and climate in the southwestern United States. 1979. Van Devender, T. R., and W. G. Spaulding. Science 204:701-710.

Ecology of Phreatophytes,  Frank M. Thomas. 2014. ex. Progress in Botany. ISBN 9783642387975 9783642387968 Accessed on Sept. 25, 2016.

Ecosystem Function of Biodiversity in Arid Ecosystems. L.F. Huenneke and I. Noble. Accessed on Sept. 25, 2016.

Low Impact Development. Accessed September 27, 2016.

Mojave Desert Ecosystem Program: Mojave Vegetation Mapping Project. Kathryn Thomas,   Peter Stine. U.S. Department of the Interior | U.S. Geological Survey. Accessed September 27, 2016.

Mojave Desert Wildflowers: A Field Guide To Wildflowers, Trees, And Shrubs Of The Mojave Desert, Including The Mojave National Preserve, Death Valley. March 5, 2013. Pam Mackay.

Outline of ground-water hydrology with definitions. Meinzer, O.E. 1923. U.S. Geological Survey Water-Supply Paper 494.

Overview of the Mojave – Plant Adaptations. Walter Feller. ex. Desert Gazette, Accessed on Sept. 25, 2016.

Plants as indicators of ground water. 1927. Meinzer, O.E. U.S. Geological Survey Water-Supply Paper 577.

Preliminary descriptions of the terrestrial natural communities of California. 1986 Holland, R.F. State of California, The Resources Agency, Nongame Heritage Program, Dept. Fish & Game, Sacramento, California.

Presentation Abstracts Mojave Desert Science Symposium. Urban effects/Pollution. February 25-27, 1999 Michael F. Allen.   Center for Conservation Biology, University of California Riverside, CA 92521-0334  Accessed on Sept. 25, 2016.

Rain garden. September 1, 2016. Wikipedia. Wikimedia Foundation. Accessed September 27, 2017.

Rain Gardens. LA Stormwater | LA’s Watershed Protection Program. Accessed on Sept. 27, 2016.

Restore nature one garden at a time. Calscape.  1999-2014. California Native Plant Society. Accessed September 27, 2016.

Seed Propagation of Native California Plants. Dara E. Emery. Santa Barbara Botanical Garden.

Soak Up the Rain / Rain Gardens. Last updated on September 8, 2016.  United States Environmental Protection Agency (EPA). Accessed on Sept. 25, 2016.

SoCal LID Manual. Low Impact Development Manual for Southern California: Technical Guidance and Site Planning Strategies. 2016. California Stormwater Quality Association

The California Deserts: An Ecological Rediscovery. July 2, 2008.Bruce M. Pavlik. University of California Press. ISBN: 9780520251458

The Desert Environment. 1985. Evenari. In Hot Deserts and Arid Shrublands. Vol. A. Ecosystems of the World. Vol 12A. Amsterdam ; New York : Elsevier ; New York, N.Y., U.S.A. : Elsevier Science Pub. Co., 1985-1986.

The Jepson Desert Manual: Vascular Plants of Southeastern California. March 28, 2002. Bruce G. Baldwin (Editor), Steve Boyd (Editor), Barbara Ertter (Editor), Robert Patterson (Editor), Dieter H. Wilken (Editor), Margriet Wetherwax (Contributor). University of California Press. ISBN: 9780520227750

Vegetation and floristic diversity in the Mojave Desert of California: A regional conservation evaluation. 1996. Thomas, K.A. .  Dissertation. University of California, Santa Barbara, California.

Vegetational and climatic development of the Mojave Desert: the last glacial maximum to the present. 1990. Spaulding, W. G.  Pp. 166-199 in J. L. Betancourt, T. R. Van Devender, and P. S. Martin (eds.). Packrat Middens: The Last 40,000 Years of Biotic Change. University of Arizona Press, Tucson.

About Caliche Chick

I retired from a career as an Environmental Scientist and Botanist. My first career was teaching science and English as a Second Language (ESL), and content classes for ESL students at the middle school level. I also taught introductory biology at the community college level. I have an avid interest in plants that grow with little to no irrigation. I also keep a vegetable garden, fruit trees, and back yard chickens. When I am not in my yard, I am taking Construction Technology Classes at Victor Valley College and working on my "fixer upper" home.
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