Tom Karwin, on gardening | Uncommon Plant Selection – Santa Cruz Sentinel

Take care of your garden

Recent columns have focused on my naming of the five most popular groups of garden plants. Some or all of these plant groups are included in my garden and many other gardens.

Generic groups (dahlias, irises, and roses) include growing lists of varieties selected or hybridized by growers to appeal to gardeners; the other groups (California natives and succulents) include both many genera and species and different varieties.

Overall, these popular plant groups offer a large number of options to choose from, making plant selection a difficult task for many gardeners. We suggested making this task easier by buying plants that would (a) align with a thematic design for the garden, and (b) grow to an appropriate size for a specific spot in the landscape.

Here’s a third approach: select uncommon plants that you like.

It’s a liberating way to select plants while taking on new challenges to identify and find rare plants that appeal to your eyes and then find them in the right places in the garden.

These new challenges can be enjoyable pursuits. They consist of leafing through the pages of mail order catalogs, browsing sections of a garden center and browsing websites on the Internet.

I have enjoyed such scavenger hunts, with the result that the popular plant groups in my garden are supplemented by several uncommon plants. These are not very rare plants, but specimens that differ from more familiar plants, and are exceptions.

Here are some examples.

Ornamental onion (Allium schubertii). This bulbous perennial is native from the eastern Mediterranean to Central Asia. In the spring, it produces 12-inch-wide umbrella-shaped flower heads (umbels) that can be compared to exploding fireworks. Its dried seed heads fall to the ground where they are spread by the wind, earning it the plant’s other common name, Tumbleweed Onion. This eye-catching plant will self-seed to a limited extent, and each season’s new crop is pleasing to the eye. It can be found in mail order catalogs that feature Alliums and other bulbs.

Madeira Island Geranium (Geranium maderense). This plant is the largest of the 422 species of the genus Geranium. It blooms every other year, but its dark green webbed leaves deserve pride of place in the garden when not in bloom. When it blooms in the spring, its huge inflorescence of 1-inch-wide dark mauve-pink centered flowers rise to five feet, well above the 3×3 foliage. I acquired this plant in the fall of 2017, in Santa Cruz Garden Exchange. It has since grown and proliferated well, producing seedlings for other Garden Exchange visitors. I recently lifted a large seedling for a friend and then watched the lower leaves shrivel as the plant developed roots. It looks healthy now, but I’ve since learned that the lower leaves are needed to support the towering flower heads. Time will tell if loss of lower leaves will be a problem.

Globe daisy (Globularia sarcophylla ‘Blue Eyes’). This relatively rare plant is endemic to the Canary Islands. It is a shrubby perennial, reaching 3×3 feet with dark green 2 inch long dark green leaves. Its appeal centers on its unique 1-inch-wide, globose flowers with white petals with lavender-blue margins that bloom from spring through summer. This plant was hybridized by the Huntington Botanical Gardens and is grown by San Marcos Growers (which supplies local garden centers).

Rice flower (Pimelea ferruginea ‘Bonne Petite’). This Australian native grows to a 3×3 foot evergreen bush, with generous clusters of small pink flowers that bloom most profusely in spring. The species name means “rust-colored”. The plant grows well in a sunny location with well-drained soil. I acquired this plant about three years ago at the UC Santa Cruz Arboretum and Botanical Garden. It grows well but apparently doesn’t have a long lifespan so I’ll enjoy it until a replacement is needed.

Advance your knowledge

The Cactus & Succulent Society of America will present the webinar, “The Succulent Collection from Babylonstoren Farm,” at 10 a.m. Saturday. This is an outstanding garden in the Western Cape in South Africa, focusing primarily on southern African succulents, and run as a botanical garden. The presenter, Ernst van Jaarsveld, Ph.D., was employed by the South African National Biodiversity Institute from 1974 to 2015. As a horticulturist, he curated the succulent section of the famous Kirstenbosch National Botanic Garden . After his retirement, he pursues a full-time job at the Babylonstoren farm and helps build a succulent collection like a botanical garden. Jaarsveld is the author of over 200 articles and several books. In 2013, with Uschi Pond, he produced a small book on Welwitschia mirabilis to commemorate the 100th anniversary of the Kirstenbosch Botanical Garden. He is also the author of Tree Aloes of the World (2015). Ernst is a member of the Cactus and Succulent Society of America. To register for this free event, go to


The Monterey Bay Rose Society will present its 41st Annual Rose Show, from noon to 5 p.m. Saturday, at the Alladin Nursery, 2905 Freedom Blvd., Watsonville. This in-person event features roses expertly grown by local gardeners and provides an opportunity to discover and select roses to purchase from a variety of sources during the upcoming bare root season.

The California Landscape and Garden History Society will be sponsoring the webinar, “Garden History of the Monterey Peninsula,” at 6 p.m., May 11. For more information on this paid event and to register, go to and click on “Events”.

Enrich your gardening days

Try sprucing up your garden by organizing scavenger hunts for unusual plants. While we can always appreciate familiar plants, having “something different” could add spice to your garden design. It might also catch the eye of your gardening friends.

Enjoy your garden!

Tom Karwin is Past President of Friends of the UC Santa Cruz Arboretum and the Monterey Bay Iris Society, Life Member of the Monterey Bay Area Cactus & Succulent Society, and UC Life Master Gardener (certified 1999-2009). He is now a board member of the Santa Cruz Hostel Society and active with the Pacific Horticultural Society. To see daily photos of her garden, For information on gardening coaching and an archive of previous On Gardening columns, visit Contact him with comments or questions at [email protected].

Comments are closed.