Quarryhill Botanical Garden

 

There is a largely unknown horticultural gem set in the flank of the Mayacamas foothills above Glen Ellen in the Sonoma Valley. A place of serpentine gravel paths wending through glades of flowering shrubs, under shading boughs of exotic trees, past tranquil ponds with burbling waterfalls, and over and down rolling hillocks of rocky decomposing volcanics.      

It’s a place of varying beauty at all seasons, from the riot of flowers in spring, through summer’s lush green serenity, into fall’s bounty of color, and even in the stark, barren leaflessness of winter, when visitors can glory in the variegated and striped bark, red and maroon branches and colorful, scarlet, orange and lavender berries. I’ve become strongly attached to this beautiful place since becoming a volunteer about a year ago.

Quarryhill Botanical Garden is a wild, temperate, Asian woodland garden. It is not manicured, is minimally pruned and intentionally has quite a natural feeling. There are two general groups of Asian plants: the Sino-Japanese and the Sino-Himalayan, and those groups come together in southwestern China, from which a great many of the garden’s plants come--so this garden is, in effect, a re-creation of the wild woodlands there.  Quarryhill is the closest that most people can come to visiting the wilds of Asia. Impressively, Quarryhill contains one of the largest collections of scientifically documented, wild-source Asian plants in North America and Europe--approximately 22,000 plants, including over 1250 individual species— so it is really a living museum of Asian flora. These plants represent the ancestors of horticultural favorites found throughout the western world: roses, camellias, peonies, magnolias, rhododendrons, maples and many more.

Some really important, rare, and/or endangered species thrive in the garden: Illicium Simonsii is a rare and unusual flowering shrub; the Magnolia sinica is one of only two in north America, and only twelve remaining in the world; Emmenopterys Henryii is one of only two to have ever bloomed outside of Asia; Acer pentaphylum from western Sichuan is the rarest and most endangered maple in the world—Quarryhill is a participant in a project to attempt to save it from extinction. In addition, two of the garden’s beautiful, large, rambling roses, Rosa chinensis var. spontanea and Rosa odorata var. gigantea are the key parent roses of all hybrid tea roses. 

Quarryhill was the idea and inspiration of Jane Davenport Jansen some twenty years ago. An east coast restaurant heiress, transplanted to San Francisco in the 60’s, she bought the original forty acres in 1968 as a summer house. She planted a fairly standard garden around the house, a few acres to grapes for wine, and like many people, visited the Sonoma Valley as a part time vacationer. A strong-willed woman of bold ideas, in 1986 she met Englishman Lord Charles Howick, and learned of the new arboretum he was creating at his family estate in Northumberland, and quickly thereafter decided that she wanted to create a botanical garden herself. She hired noted Napa landscape architect Roger Warner to lay out the garden, and local landscaper William McNamara to work on installation. McNamara would become more and more involved with Quarryhill, and ultimately become its Executive Director.

In the spring of 1987 Jansen came to a joint agreement with Howick and the Royal Botancial Garden at Kew, in England—one of the world’s largest, and arguably most important botanical gardens—to mount a joint plant-collecting expedition to southwestern China. Kew had become quite interested in China and had obtained permits to visit and collect seeds and plant specimens.

Quarryhill boasts an illustrious Board of Advisors, including the aforementioned Lord Howick, the renowned Director of the Missouri Botanical Garden Peter H Raven, and Anthony Kirkham, the Head Arborist at Kew. I visited Kew last year and, courtesy of an introduction by Bill McNamara, was given a wonderful private tour by Tony. He related some interesting facts about the early joint collecting trips.  “We were very interested in collecting in China, which had just opened to the west after forty years” said Kirkham “but, believe it or not, as large and important as Kew is, we didn’t have the funds for an expedition. We had the contacts in China and the permits, and Jane had the money and was willing to underwrite the first expedition, and that’s how the collaboration was born.”  That was McNamara’s first Asian expedition, and he brought back plant specimens and seeds, which were germinated in a temporary greenhouse. Finally, in 1991, the first plants went into the ground—substantially all from 4 inch pots.

Bill McNamara, who has been Executive Director for some years now, and who has led each annual collecting expedition to Asia, says “there is an extinction crisis looming, that while much talked about in regard to animals, is rarely mentioned where plants are concerned. Estimates of currently-living plant species vary from 300-450,000, and botanists speculate that forty to fifty percent of those may be extinct by the turn of this century.”  Both soft-spoken and passionate, he continues, ”this is caused primarily by habitat loss due to the rapidly expanding human population, and its consequent urban and agricultural expansion—and as we know, that expansion in Asia, and China especially, is accelerating.  So the promotion of the knowledge of this plant diversity loss, and the necessity and benefits of conservation, both in the wild, and in gardens such as Quarryhill are a couple of the key reasons for our being, and one of Jane Jansen’s primary legacies.”

There has been a collecting expedition every year—often in collaboration with Kew, Howick Arboretum, and/or Edinburgh Botanical Garden—covering China, Nepal, Tibet, Japan, Taiwan, Korea or India. Seeds are collected for propagation, as well as herbarium samples (leaves, twigs, fruits and flowers dried and pressed in a plant press). “Documented, wild-source plant materials--no hybrids, no crosses, no nursery plants—are what most researchers require for their projects, which include DNA analysis, molecular studies, phylogenic and distribution studies” relates McNamara, and these samples are shared with other prestigious institutions including UC Berkeley, the Morris Arboretum at the University of Pennsylvania, the Arnold Arboretum at Harvard, the Missouri Botanic Garden, University of British Columbia and the US National Arboretum.

What exists today—a mature, world-class botanical garden with full size trees to 65 feet tall shading glades and copses of temperate Asian plants—all grown from those four-inch pot seedlings is an amazing accomplishment in just seventeen years. The garden is a tribute to management, its staff, a small clan of dedicated volunteers, and to the vision, will and audacity of Jane Jansen herself.

I saw a call for new volunteers in the local newspaper late last summer, and enrolled in the docent-training program in the fall. The enthusiastic, committed band of volunteers includes propagation volunteers, who assist Head Nurseryman Corey Barnes in the growing of seeds, propagation and planting of plants, and tour docents, whose ranks include Press Democrat gardening columnist and author Rosemary McCreary, garden writer Janet Sanchez and current Sonoma County Master Gardeners board president Linda King. Bill McNamara emphatically states “we couldn’t do what we do at Quarryhill without our great volunteers”.

Six full-time gardeners, led by head gardener Sal Calderon, who started in 1987, tend the garden’s twenty-plus acres: planting, maintaining the irrigation system, weeding and cutting back in fall. Almost no fertilizing or soil amending is done, and little pruning—just enough to keep the trails and paths clear, but not so much as to change the wild nature of the garden. McNamara says “the decomposing volcanic soil is very well drained, and that has contributed greatly to the success of the garden—since these are plants from summer rainfall/dry winter climes, poorly drained soil would have made it much harder for them to survive our wet winters.”

Docents are often asked “what is the best time of year to visit Quarryhill?” by visitors expecting a single answer.  I always tell them that there is no best time, and that they should visit at least four times per year to see the garden in all its states.

Starting this year, the garden is open to the public year-round. Self-guided tours are available Mon-Sat 9 am – 4 pm, for a small donation of $10 per person, and include a keyed map with descriptions of some of the most important plants. Docent-led tours, concentrating on significant plants and habitat, are conducted every third Saturday morning, with reservations recommended. Private tours are available for groups six or more by advance reservation of two weeks. Quarryhill hosts several events every year, including an informational tour series with Director McNamara, one or more full-moon hikes, lectures by visiting luminaries of the horticultural world, and an annual Spring Celebration—part garden party, part rare plant auction, part garden tour series.

At this year’s Spring Celebration, lauded British horticulturalist Sir John Simmons, OBE, VMH, (the first refers to a British Knighthood, and the second signifies a holder of the Royal Horticultural Society’s Victoria Medal of Honor, of which there are only 37 in the world) gave the keynote address. A long-time friend of Quarryhill, Sir John related captivating stories of plant collecting in the wilds. We docents led many tours of the garden for some of the 230 people that attended. My final tour of the day included noted Bay Area arborist Barry Coates, who introduced me to his friend and associate, the eminent landscape architect Steven Suzman, saying “here is one of the few landscape architects that actually likes plants”. Despite having seen hundreds of gardens between them, and knowing literally thousands of plants, they were enthralled and fascinated by Quarryhill, and found things that were new to them both. 

So if you’re a garden buff at all, just think that if such experienced lions of the horticultural world can find wonder and delight at Quarryhill, what an amazing experience it will be for you. Come soon.