Almost exactly one year ago, this column featured Mangaves, new succulent plants for the garden. Mangaves are new plants because they are crosses between two well-established Mexican plant genera: Agave and Manfreda.
Today’s column revisits the Mangaves for two reasons. First, the Cactus & Succulent Society of America recently published a thorough review of the origin of this hybrid plant and an overview of the development of new cultivars.
Second, we can observe the past year’s growth and update appropriate care for these plants.
The CSSA article, “Magnificant Magaves,” appears in the Summer 2022 issue of the Cactus and Succulent Journal. This quarterly publication is not available online, so we’ll provide highlights from the article.
The article’s author, Tony Avent, and his wife Anita are the owners of the extraordinary Juniper Level Botanic Garden and Plant Delights Nursery in Raleigh, North Carolina. They have gifted this awesome project to North Carolin State University, to be linked to the existing JC Raulston Arboretum. The Avents and NCSU are working to ensure the continued operation of this unique resource.
Tony Avent is an exceptional plantsman. I had an opportunity to visit his 10-acre Plant Delights Nursery several years ago, as a side trip during travel for other purposes. The stunning diversity of the plant collection is a long-held memory and supports Garden Design magazine’s recognition of Plant Delights as one of the top seven online plant nurseries in the United States. Visit the Nursery online at www.plantdelights.com/.
In his article, Avent notes the 2003 discovery of a natural cross of Agave and a Manfreda, described as a bi-generic hybrid. This combination created a new variety that was later named ‘Macho Mocha’.
Avent then traces the work of several American hybridizers who crossed selected species of Manfreda and Agave plants to produce a range of new cultivars. Hybridizers who were particularly productive include Hans Hansen, who introduced numerous new Mangaves from Walters Gardens in Michigan.
Hybridizers in other countries soon joined the exploration of this bi-generic hybrid. One early example by an unknown breeder in Southeast Asia is Mangave ‘Bloodspot’, a hybrid of A. macroacantha and M. maculosa. This is a small plant, compared to the typical Mangaves, which grow two feet wide. (By comparison, some Agaves can reach seven feet high and fourteen feet wide.)
Succulent gardeners have welcomed Mangaves because they have attractive colors and patterns, lack spines, flower after only two or three years of growth, and, although they die after flowering, produce new generations of offsets. They grow best in full sun, which supports the coloration.
One downside of Mangaves is their relatively soft leaves which makes them vulnerable to snails. Fortunately, Mangaves are well suited to containers, which usually discourage snails, and gardeners have access to Snarol, an effective non-toxic snail bait.
Avent reports that “the proverbial flood gates opened for this new genus of succulents, which are now being gobbled up worldwide as fast as production will allow.” He also states, that Mangaves “are rapidly becoming landscape staples in non-frosting climates’ which includes much of California and other parts of the world.
Future development of these plants, Avent predicts, will yield more winter hardy selections. He lists numerous cultivars that will survive in Haridness Zones 7 and 8, which are colder than the Monterey Bay area’s Zone 9.
For Monterey Bay area gardeners, the growing number of winter hardy Mangaves means that the market for these plants will increase larger and faster than it already is growing, and hybridizers will respond to market demand by creating additional cultivars.
If you enjoy Mangaves in your garden, you already have access to multiple options and can anticipate having many more variations of this plant in the future. They are increasingly available in local garden centers. Broader selections can be found at Plant Delights Nursery (mentioned above), madaboutmangave.com, and mountaincrestgardens.com.
Advance your knowledge
The Plant Delights Nursery has a well-stocked collection of short video presentations on selected aspects of gardening. I have only set a time t https://mountaincrestgardens.com/ o begin learning from these videos, with confidence that they will be solidly based on horticultural knowledge and well worth the viewing time. There are too many titles to list here, but they are available for free viewing at www.youtube.com/c/Plantdelights.
The Ruth Bancroft Garden has announced a series of webinars for June. The following descriptions are from the RBG website (lightly edited for this column).
“Essential Trees & Palms in Dry Gardens,” 10 a.m. June 11. When planning or planting a garden the first thing to consider are the large-scale plants such as trees and palms. Tree and palm selection sets the tone for the entire design and helps determine all the other plantings. This lecture will consider how to select a tree/palm for both aesthetics and local conditions and review a wide range of commonly available drought-tolerant trees and palms. Brian Kemble, Curator, will feature plants from the Ruth Bancroft Garden plant collection, and Landscape Designer Cricket Riley will discuss how to incorporate trees and palms into a dry garden design.
“Materiality in Gardens: Design & Environmental Stewardship,” 10 a.m. June 15. Landscape Architect Jennifer de Graaf will discuss the sustainable choices you can make when selecting and using recycled materials in your garden. Focusing on the non-plant elements in garden design, she will discuss how the selections we make for our outdoor spaces have farther-reaching implications. What do you need to consider when removing or changing the paths, furnishings, etc.? We will talk through a thought path for these decisions and how to choose a material that is right for your application. The goal is to be aware of the lifecycle of a product or material, its environmental relationships and durability, and the ways a recycled material may or may not provide the aesthetic desired. Recycled materials can go from looking haphazard to intentional.
“Proteaceae & Pals (2-part series): 10 a.m. June 18 and June 25. Troy McGregor, owner of Gondwana Flora and Waltzing Matilija, will discuss plants in the Proteaceae family (e.g., Protea, Leucadendron, Leucospermum, and Grevillea). For the June 18th lecture “Proteaceae & Pals – Overview”, Troy will focus on the tried & true performers, a few new releases, and some rarities that have excelled at the Ruth Bancroft Garden.
For the June 25th lecture, “Proteaceae & Pals – Care & Maintenance,” McGregor will guide you on best planting practices, pruning recommendations, fertilizer amendments, and soil/water requirements for these Australian and South African plants.
Mitigating Fire Risks Through Garden Design & Maintenance (2-part series), 10 a.m. June 22 and June 29. Many California residents are bracing for another season of catastrophic wildfires this summer. With climate change and shifts in land management, the intensity and regular occurrence of wildfires will be inevitable in our environment. The decisions that we make in our own gardens can make a bigger impact than most people realize. Join Landscape Architect Jennifer de Graaf for this two-part series about how a multi-faceted, interconnected lifetime of decisions in your landscape can help mitigate your risks versus fire.
To register for these fee-based presentations, visit www.ruthbancroftgarden.org/events/.
Enjoy your garden!
Tom Karwin is past president of Friends of the UC Santa Cruz Arboretum and the Monterey Bay Iris Society, a Lifetime Member of the Monterey Bay Area Cactus & Succulent Society, and a Lifetime UC Master Gardener (Certified 1999–2009). He is now a board member of the Santa Cruz Hostel Society, and active with the Pacific Horticultural Society.