Thankful for plants of the Mediterranean region
Care for your garden
This week’s installment for the current planting season focuses on the Mediterranean region, which includes 17 European, African and Asian countries surrounding the Mediterranean Sea, as well as the Madeira Archipelago and the Canary Islands, nearby in the Atlantic Ocean.
Monterey Bay area gardeners favor plants that are native to a Mediterranean climate, characterized by mild-to-cool, rainy winters and warm-to-hot, dry summers. This climate is named for the Mediterranean region, but that label can be distracting because a similar climate occurs in coastal California, the southern coast of South Africa, the western coast of central Chili, and the southwestern areas of Australia.
A better, more meaningful label for this climate is “summer-dry.”
Each of these summerdry regions have distinctive native plants, so thematic gardening could devote an area within the landscape to the plants of one of these regions. This plan invites showcasing the plants of a selected region and benefitting from their common cultural requirements. The UC Santa Cruz Arboretum & Botanic Garden (arboretum.ucsc.edu/) and the UC Botanical Garden at Berkeley (botanicalgarden.berkeley.edu/) are examples of this approach in public gardens.
Public botanic gardens often organize their outdoor areas according to geographic areas such as the summer-dry areas. Some botanic gardens have an environment for, and an interest in, Asian gardens, which combine
distinctive plants and a distinctive landscaping style. The Huntington Botanical Gardens (www.huntington.org/gardens) include both Japanese and Chinese gardens.
The total land area of the Mediterranean region hasn’t been specified in the literature that I’ve seen, probably because it does not align with well-documented political boundaries. The several summer-dry climate areas add up to a small (perhaps 5%) part of the world’s total arable land, i.e., land fit for growing crops. That makes them special for gardeners.
The summer-dry climate within the Mediterranean region has considerable variation, given differences in elevation and other factors. Also, some horticulturalists have de
scribed three sub-types of this climate: cool, warm and hot summers.
Given this variation, a Mediterranean region of a garden, whether a small or large space, is unlikely to group companion plants, meaning those that grow together in nature. While it would be possible to develop such a garden, simply grouping plants that are native to the region is enough to illustrate the category and respect their common cultural needs.
The most iconic plants of the Mediterranean region are lavenders (Lavendula), figs (Ficus carica), and olives (Olea europaea). There are many other, less familiar genera that are native to this botanically rich region.
The following plants, randomly selected from my garden, are a small sample of the diverse horticulture of the Mediterranean region. Hopefully, they will suggest the region’s character and interest gardeners to include a selection of the region’s plants in their own gardens.
European Grey Sedge (Carex divulsa). This evergreen, clumping, grassy plant enjoys partial shade, tolerates boggy soils, and, when established, is fairly drought resistant. It grows to 2×2 feet or more, spreads slowly, and provides an attractive complement to many other plants. It has been mistaken as a California
native, and marketed as Berkeley Sedge, but it is a wide-ranging European species.
Rose Rose (Cistus species). This plant is native to Spain and Portugal, hybridizes naturally, has been popular with gardeners since 1860, and is available in 19 species and numerous cultivars. Popular varieties include Silver Pink Rock Rose (C. argenteus ‘Silver Pink’), White Rock Rose (C. ladanifer ‘Blanche’), and Crimson-Spot Rock Rose (C. ladanifer maculatus). These are short-lived plants that produce flowers in June and July, seed profusely and propagate easily from cuttings. Pinching back after flowering helps to maintain a bushy form.
Corsican Hellebore (Helleborus argutifolius). This is a robust plant with pale green, cupshaped flowers in late winter to early spring, and attractive leathery foliage. It grows to 4 feet tall and 3 feet wide, making is larger than most Hellebores, which are usually just 18 inches tall. After being cut back hard after flowering, it produces attractive new growth in the fall. This species is known for seeding numerous new plants each season.
Madeira Island Geranium (Geranium maderense). This largest of the Geranium species, is a bineenial 3-foot x 3-foot plant that displays attractive foliage between flowering years. When it flowers, it displays a stunning mass of 1-inch wide mauve-pink darkcentered flowers, rising to five feet. There is also a white-flowered form (G. m. ‘Alba’).
Tall Bearded Iris (Iris ‘That’s All Folks). The
Iris family includes several versions of bearded irises (grouped by height), variations of Iris germanica, a natural hybrid of I. pallida and I. variegata. This plant was first identified in 1753 and has been hybridized into 60,000+ cultivars with an extraordinary range of colors, color combinations, and flower forms. Iris lovers are challenged to keep with the latest introductions. One of my favorites is ‘That’s All Folks’, which was hybridized in Santa Cruz and honored with many awards, including the top-ranked Dykes Medal.
Variegated Lavender (Lavandula x allardii ‘Meerlo’). As already noted, the Lavender is long associated with the Mediterranean region, and appreciated for its appearance, fragrance, and moth deterrence. Several popular species include English Lavender (L. angustifolia, which is in fact native to Spain, France, Italy, Croatia), French Lavender (L. dentata), and Spanish Lavender (L. stoechas). My garden includes several English Lavender plants, but I particularly like L. x allardii ‘Meerlo’, which is selection from the hybrid of L dentata x L. latifoila.
Giant White Squill (Urginea maritima/ Drimia maritima). This plant is quite the performer. It produces wide, 18-inch leaves from November to summer. The
leaves then fade away, and from summer to fall the plant generates a four-foot stalk flower stalk with an inflorescence of a vast number (who’s counting?) of star-shaped white flowers that attract birds and bees. In this process, the large bulb (up to 12’ wide) splits dichotomously, increasing to two bulbs, and eventually forming a large clump.
Advance your gardening knowledge
Upcoming webinars: The Cactus & Succulent Society of America will present the webinar, “Yuccas,” at 10 a.m., Saturday. Yuccas are generally large evergreen plants native to hot and dry areas of Mexico and the Carribean. They are popular for dramatic elements in the landscape, and large displays of white or whitish flowers. Brian Kemble, curator at the Ruth Bancroft Garden in Walnut Creek, and a prolific author and speaker on succulent plants, will share his knowledge of Yuccas growing in habitat. To register for this free event, visit cactusandsucculentsociety.org/.
The Garden Conservancy presents webinar, “Beyond Wild: Gardens and Landscapes,” at 11 a.m. Dec. 2. Garden Designer Raymond Jungles will describe his most impactful design projects, which are also featured in his new book of the same title. To register, visit www.gardenconservancy.org/, click
on Virtual Programs and then on “Fall 2021 Literary Series.” For the Garden Conservancy’s upcoming webinars, click on “Winter/Spring 2021 Virtual Programs.”
The UC Botanical Garden at Berkeley has announced its December program of webinars. Early offerings include “Virtual December Butterfly Walk — Beyond the Bay Area,” (11 a.m., Dec. 5) and “Winter Conifers Virtual Tour” (3 p.m., Dec. 7). For information on these free events and other virtual programs, visit botanicalgarden. berkeley.edu/, click on “Programs” and then on “Programs & Workshops.”
Enrich your gardening days
Consider developing your own collection of plants from the Mediterranean
Basin. There are both familiar and pleasingly different plants to enhance your garden.
Enjoy your garden!
Tom Karwin is past president of Friends of the UC Santa Cruz Arboretum, Monterey Bay Area Cactus & Succulent Society, and Monterey Bay Iris Society, and a Lifetime UC Master Gardener (Certified 19992009). He is now a board member and garden coach for the Santa Cruz Hostel Society. To view daily photos from his garden, https://www.facebook.com/ongardeningcom-566511763375123/. To search an archive of previous On Gardening columns, visit http://ongardening.com. Contact him with comments or questions at tom@karwin.com.