Our Collection
Collection History
In 1968, philanthropist and plant enthusiast Jane Davenport Jansen purchased the Garden’s current site. Around her wine country home, she planted Cabernet Sauvignon grapes on the valley floor and began to take an interest in the upland parcel, the site of an abandoned sandstone quarry.
With the shift in U.S.-China relations during the 1970s and 80s, new garden plants arriving from China sparked enormous interest. At the same time, China’s rapid industrialization began to significantly threaten its temperate flora. Recognizing a unique global conservation need, Jansen funded a series of seed-collecting expeditions to Asia in partnership with the Royal Botanic Gardens, Kew in London, and the Howick Arboretum in Northumberland.
By the spring of 1990, young plants grown in the Garden’s nursery from these wild-collected seeds had been planted on the hillsides above the vineyard. Annual collecting expeditions continued until 2017, and today, Sonoma Botanical Garden is home to one of the largest collections of scientifically documented, wild-source Asian plants in North America, many rare and endangered.
In 2021, the Garden embarked on a new initiative to add a focus on California’s rich native flora, another biodiversity hotspot facing many of the same challenges that inspired Jansen to conserve Asian plants in the 1980s.
With its 20,000 individual plants, representing almost 1,500 different species, the Garden is a rich repository for the preservation, enjoyment, and study of unique and rare plants. We actively continue to build our collection, prioritizing those species that are wild origin, threatened in their natural habitats, and that best enhance our mission.
Blue Oak
(Quercus douglasii)
Great Magnolia
(Magnolia grandis)
Firecracker Rhododendron
(Rhododendron spinuliferum)
Collection Highlights
(Magnolia delavayi)
Magnolias
The Garden’s many lovely Asian magnolias, with nearly 50 species and over 150 plants, are some of the stars of the collection. These iconic and ancient plants exhibit more diversity than first meets the eye, ranging from large trees to medium shrubs—some deciduous, some evergreen. A number of species bloom dramatically on bare branches in the chilly, late winter, while others flower in the warm months of May and June. The often large, impressive buds can be protected by thick, furry, grey scales or covered in coppery hairs that shine in the sun. Even when not in bloom, the foliage can be stunning, with the leaves of the Garden’s many different species varying widely in size, texture, or color of new growth.
Maples
The majority of the just over 50 species of Maple at the Garden are rarely grown commercially and thus not often seen by the public. 87% are wild origin documented, making them a tremendous resource for study and research. Their striking autumn color, in hues of yellow, orange, and red, are a seasonal delight, but these magnificent trees offer visual interest throughout the year. From their fuzzy, emerging, fresh leaves to brightly colored or long, drooping chains of developing seeds, the everchanging beauty of the Garden’s maples can be experienced in all seasons.
(Acer sinense)
(Rosa moyesii)
Roses
The Garden’s beautiful collection of Asian roses falls into two distinct categories. In the formal Jiang Entian Chinese Heritage Rose Garden, there are nearly 100 complex rose hybrids showcasing the role Chinese species have played in transforming rose hybridization. Then, planted throughout the Garden’s Asian woodland, there are over 35 species that highlight the diversity of wild roses, a plant group few ever get to see. These are species that have been shaped by nature and tuned by their habitats. From April to July, these plants, from large climbers to delicate shrubs, bloom in a sequential parade, covered in brilliant, fragrant flowers.
Rhododendrons
With a myriad of colors, shapes, textures, and sizes both in flower and foliage, there is a rhododendron for every imagining. With over 60 species, the collection at the Garden showcases this diversity by introducing many that are rarely seen. This truly diverse plant group has well over 1,000 species in the wild with most from southeast Asia. The variety is breathtaking—from leathery-leaved trees ablaze with large, blood-red flowers to low ground huggers with tiny, bright yellow flowers. While many species do bloom in the spring, a good number flower in winter, with others just getting started in early summer.
(Rhododendron arboreum)
Turk’s Cap Lily
(Lilium leichtlinii var. maximowiczii)
Lilies
With nearly a dozen species in the collection from Japan to central and southwest China, you can often find spectacular lilies in bloom at the Garden throughout the summer, from the first warm days in May until the crisp cool of November. The large and dramatic, trumpet-like blooms with purple or deep orange spots stand in clusters on their single leafy stems wafting a sweet fragrance into the summer air. Most of the species at the Garden retain their wild-documented provenance, helping to preserve the living genetics of these plants.
Conifers
The Garden’s unique location—with ideal temperatures, moisture, and drainage—is hospitable to many plants in the collection, but particularly so to its wide range of rare pines, cypress, yews, and other conifers from a vast array of habitats, excluding the most extreme. Some of Earth’s most ancient plants, this tremendously varied group can be naturally found in habitats from frigid temperate to lowland tropical. Fully one third of the over 100 species of Conifer in the Garden’s collection have reached a level of endangered status in the wild. Whether growing as towering trees or ground hugging mats, the specimens in the collection deepen an appreciation of just how majestic these plants can be, no matter how large or small.
(Thujopsis dolabrata)
(Diplacus aurantiacus)
California Natives
Representing the ecological heart of Northern California, the Garden’s surrounding native oak woodland and savannah are defined by majestic valley, coast live, and blue oaks, open grasslands, and diverse understory plants such as Pacific hound’s tongue and shooting star. Where the landscape turns to shrub-dominated chaparral, natural stands of manzanita, scrub oaks, and chamise grow densely. This native landscape supports a rich variety of wildlife and, importantly, stores carbon. A California native demonstration garden at the Welcome Center showcases the use of water-wise, fire resilient, and commercially available native plants for landscaping.
Cabernet Sauvignon Vineyard
The Garden’s 13-acre, legacy vineyard showcases the iconic red wine grape of California. Cabernet Sauvignon thrives in Sonoma’s climate and soil, producing bold wines that reflect the region’s agricultural heritage. In 2023, vineyard partner, La Prenda Wines, achieved organic certification and released the first publicly available wine produced from this vineyard.
(Vitis vinifera)
Oliver Maple
(Acer oliverianum)
Chestnut Rose
(Rosa roxburghii fma. normalis)
Taiwan Plum Yew
(Cephalotaxus harringtonia var. wilsoniana)