From Walnut Creek to the Algarve: gardening with succulents and native plants

In Walnut Creek, California, north of San Francisco, is a magical garden where, for the last 47 years, succulents and cacti, interspersed with trees and native plants, have grown and thrived to become a fascinating wonderland and an impressive example of what can be achieved with minimum water usage. The garden is the Ruth Bancroft Garden, and I know of it from a beautiful book, The Bold Dry Garden: Lessons from the Ruth Bancroft Garden by Johanna Silver, with wonderful photos by Marion Brenner. And there are many lessons to learn.

Walnut Creek is on approximately the same latitude as the Algarve and has a similar Mediterranean climate – cool, wet winters and hot, dry summers – and a similar level of rainfall. Therefore, what has worked for Ruth Bancroft should work here, too. And we know from the huge agaves (Agave americana) that grow wild around the area with their massive inflorescences like trees, and the prickly pear cactus (Opuntia) that also grows wherever it can, with no care from anyone, that succulents and cacti do well here. And the Ruth Bancroft Garden is an inspiration as to what can be achieved.

Like the Barrocal region of the Algarve, Walnut Creek has clay soil, so Ruth began by experimenting with what grew well on the heavy clay around her house: roses, scented pelargoniums and especially irises. She had a huge collection of irises along the driveway to the house, a photo of which is in the book.

Ruth also began collecting small succulents and cacti in pots as she so admired their form, but soon decided to try them outside. Like many of us, she had a lot of failures at first until she learned to give them good drainage.

Her big chance came in 1971, when three acres (1.2 hectares) of the family’s former agricultural land was made available to her. She had studied architecture in her youth, before she had to give it up for economic reasons, but this training proved useful in helping her to design a garden for her ever-increasing succulent and cactus collection.

The first problem was that the land was flat, and compacted heavy clay (a problem many of us know well), and her plants needed good drainage. So, with her assistants, she created hillocks of rock. This allowed the plants to be well drained and also plant groupings to be seen from different angles. The hillocks were surrounded by meandering paths, at least 3 feet wide, so people could wander easily through them.

It was, from the start, a dry garden: the land had only one well, and her husband did not want to drill more or use the city water, as even back then he understood the need to save water resources. However, dry conditions suited Ruth’s purpose and plants well.

Ruth always bought small plants, as these grew faster than those in bigger pots, established better and were cheaper. She, therefore, needed to research each plant and leave room for it to reach its eventual size. And they were slow growers. This meant that at first the planting looked a bit sparse. She needed imagination, to picture the later effect, and patience. After 50 years, many of them, including Yucca filifera, Agave franzosinii and Washingtonia filifera, have grown into giants. She planned planting groups: small succulents like tiles in mosaic patterns, larger groups contrasting structure and leaf shape and colour. Native plants and perennials provide softness and trees a canopy and verticality.

In 1972, the second year of the garden, a freak hard frost killed almost all the plants. They were newly planted, small and not established. This would have been enough to make many of us abandon the project, but Ruth was undaunted. She replanted and then experimented with what would survive, what not. She protected some plants, cut others to the ground each year. Others proved to be hardier than might have been expected.

Although most of the plants in the garden are succulents, not all are. There are many trees, for example, manzanitas, pines, Melaleuca preissiana, Ceiba speciosa (silk floss tree), and cycads, California natives and Australian plants, all of which provide variation in height, form and texture.

The book has sections on the different plants and plant groups in the garden, which make it excellent for reference: Small plants (aeonium, crassula, echeveria, haworthia, sedum, sempervirum), Architectural elements (agave, cactus – all the different shapes – yucca and other swords), Flowers and Foliage (ice plants, aloe, euphorbia, gasteria, protea, bromeliads) and the Softer Side, the bulbs, wildflowers and grasses that balance out the spikes, spines and sharp edges.

Going through the book, I constantly found myself thinking to myself: “I could do that!” or “I would never have thought of that!” or “I didn´t know that.” Not only the many plants themselves and their cultivation but also hints on design and plant combinations to make them look their best make this a book worth reading and re-reading. Not to mention the photos that show the detail and form of the plants in a spectacular way.

Ruth Bancroft started her garden at age 63. She worked in the garden until she was 100. She died last November 2017, at the phenomenal age of 109, so clearly, the garden did her good. And she was able to watch her slow-growing garden evolve and mature, a dream of gardeners everywhere.

The Bold Dry Garden:
Lessons from the Ruth Bancroft Garden by Johanna Silver. Photographs by Marion Brenner.
Published by Timber Press, Portland, Oregon, USA, 2016
Hardcover 236 pages

By Tessa Hearn

Tessa is a lifelong gardener who lives and gardens near Loulé. She is an enthusiastic member of the Mediterranean Gardening Association Portugal, where she is Events Coordinator.


Clockwise: Kalanchoe orgyalis, Echevaria hybrid, unnamed Cotyledon, Portulacaria afra, Euphorbia milii

Aloe marlothii, Arthur and Elly van Tilborg’s garden, Corte António Martins, Tavira