1979: The Urasenke Foundation of Kyoto collaborated with prominent Seattle Japanese Garden patron Mr. Prentice Bloedel to reconstruct the Seattle Japanese Garden teahouse, which had been lost to a fire in 1973.

1980: The Seattle City Council, the University of Washington, and the Urasenke Foundation of Kyoto formed a partnership to rebuild the Seattle Japanese Garden teahouse. Urasenke’s aim was to establish it as a focal point for fostering a broader understanding of Japanese culture through Chadō, the Way of Tea. 

1981: A Memorandum of Understanding for the Use and Maintenance of Shoseian teahouse in the Seattle Japanese Garden was established between the City of Seattle, the University of Washington, and the Urasenke Foundation. This agreement encompassed various activities, including classes, workshops, tea presentations, and maintenance that included daily cleaning of the interior and exterior of the teahouse and garden waiting shelter, and bi-annual deep cleaning. The shoji screens were repapered annually and every decade the tatami mats were replaced.

1981: Bonnie Sōshin Mitchell was appointed as the tea master of Shoseian by the Urasenke Foundation of Kyoto, following her studies at the Urasenke headquarters from 1975-1981.

1981: Urasenke Foundation Grand Tea Master Sen Sōshitsu XV celebrated the opening of the teahouse and named it Shoseian ‘Arbor of the Murmuring Pines.’

1981 UW Art History Professors Glenn T. Webb and Bonnie Sōshin Mitchell launch the Chadō and Japanese Aesthetics credit course, with Tea practice held in Shoseian teahouse until 1990 and lectures held on campus. The course was offered three quarters a year and funded by Urasenke Foundation from 1981-2013. It was reoffered in the Department of Asian Languages and Literature from 2017-2020.

1981 Arboretum Foundation, Unit #86, collected and planted mountain moss the roji tea garden.

1981 Mitchell initiated daily tea garden cleaning that could not be provided by the understaffed Seattle Parks Department gardeners.

1982: Mitchell installed shelves in the storage closet, and a storage platform in the crawl space beneath the kitchen mizuya.

1982: Shoseikai, Friends of the Teahouse, was formed by Mitchell, Glen T. Webb, Aiko Sōai Fujii and Chieko Sōchi Becker to welcome tea practitioners from various traditions to use the teahouse for monthly member tea gatherings.

1982: Mitchell launched monthly public Shosei’an Teahouse Demonstrations.

1983: Mitchell transferred the management of the monthly public Shosei’an Teahouse Tea Demonstrations to Shoseikai, that continued until 2018, when Shoseikai was disbanded by the Seattle Park Department who took over management of the public demonstrations and maintenance of the teahouse.

1983: Shoseikai donated a Rikyu-style two-fold screen to Shosei’an.

1984: Mitchell, in coordination with Urasenke Foundation of Kyoto, launched the first three-day Tea Ceremony Seminar for tea practitioners from Oregon, Washington, and British Columbia. The seminar was held in Shosei’an.

1985: Urasenke Foundation of Kyoto established the Seattle Branch of the Foundation (UFSB) with Mitchell as director.

1986: Mitchell coordinated a Kōdō Incense Ceremony workshop with Shoyeidō Incense Company of Kyoto and the grand incense master of the Shino tradition of Kōdō.

1987: Wm. Patterson Sōki Pope joined Urasenke Foundation Seattle Branch (1987-1993).

1987: Prof. Glenn T. Webb departed UW for Pepperdine University, and Wm. Patterson Sōki Pope replaced Webb as Chadō course lecturer (1987-2002).

1988: The second three-day Tea Ceremony Seminar for tea practitioners from the region was coordinated by Mitchell with Urasenke Foundation of Kyoto.

1989: Mitchell and Shoseikai funded the removal of grass cloth wallpaper and the plastering of plywood walls to simulate traditional earthen walls.

1989-1997: Mitchell coordinated with Sekisui House, Chanoyu demonstrations at Bellevue Square, in the teahouse donated to the City of Seattle by Sekisui House, later renamed the Nagomi Teahouse.

1990: Urasenke Foundation of Kyoto replaced the Shoseian ten tatami mats, installed an overhead light fixture, and applied paper wainscoting to the tearoom.

1991: Mitchell relocated UW Chadō studio classes to a private Madison Park residence due to the lack of onsite Garden restrooms, but continued to coordinate monthly public Tea Demonstrations and Seasonal Tea Gatherings.

1992: Mitchell and Kazuyuki Murata funded the plastering of painted plywood walls in the garden waiting shelter.

1992: Mitchell served as liaison for the installation of the Ryokusui’an teahouse in the Seattle Art Museum, donated by Urasenke Foundation of Kyoto.

1992: Mitchell coordinated the third three-day Tea Ceremony Seminar for regional tea practitioners with Urasenke Foundation of Kyoto.

1995: Mitchell launched annual Children’s Day tea ceremonies at Shosei’an teahouse.

1996: Mitchell coordinated the fourth three-day Tea Ceremony Seminar for practitioners from the region with Urasenke Foundation of Kyoto.

1997: Mitchell launched the public Sunday afternoon tea demonstrations with the service of matcha, funded by the sale of tea tickets, after 16 years of petitioning a resistant Seattle Park Department.

1999: Timothy Sōwa Olson joined UFSB as an instructor.

2002: Timothy Sōwa Olson replaced Pope as UW lecturer and lead studio instructor of the UW Chadō course.

2004: Shosei’an was the setting for a tea ceremony film produced by the Seattle Art Museum for use in the museum’s tea house gallery.

2005: Mitchell initiated participatory public Tea Gatherings with matcha as part of the Japanese Garden Advisory Council’s fundraising campaign for a new gatehouse.

2006: Mitchell led a ten-day tour for 30 tea practitioners to experience the Tea culture of Kyoto.

2006: Mitchell funded and cooperated with senior gardener James Thomas to enhance the inner and outer roji tea garden at Shosei’an.

2007: Mitchell coordinated with Urasenke Foundation of Kyoto to replace ten tatami mats, six sliding interior doors, and repaper the paper wainscoting, and shoji screens.

2008: Mitchell hosted Hounsai Sen Sōshitsu XV’s visit to Seattle, including various tea ceremonies and lectures.

2010: Urasenke Kyoto closed the Seattle Branch, which subsequently reorganized as the East-West Chanoyu Center (EWCC).

2011: Seattle Parks Department terminated the 30-year Shoseian Use Agreement with Urasenke Foundation of Kyoto and the University of Washington.

2011: Mitchell declined the City’s request to voluntarily maintain Shosei’an teahouse and garden without compensation.

2011: Mitchell transferred the calligraphic scroll “Shosei’an” brushed by Sen Sōshitsu XV to the Seattle Parks Department, Lisa Chen.

2011: EWCC donated tea ceremony art and utensils to Parks, for Parks to continue the public tea programs Mitchell developed.