[1] Endowed with an elevated southerly orientation, the upper park offers visitors a clear panoramic view of the City of Santa Barbara's coastline and the Channel Islands.

Nevertheless, the location was considered ideal for the purpose of establishing a botanical garden, as it straddled both the northern and southern slope of Mission Ridge (offering a variation of solar exposure), and was endowed with soil described by Dr. Franceschi to be "as a whole exceptionally rich, retaining moisture in a wonderful degree on account of the powerful deposit of diatomaceous earth which underlies the disintegrated sandstone.

[4] In 1927, after learning of the house during a garden tour that was suggested by Pearl Chase, the remaining 2.14 acres (0.87 ha) of the property including the mansion was sold to Alden Freeman, a wealthy Standard Oil heir, progressive reformer, philanthropist, and amateur architect.

[4] The exterior walls of the mansion were adorned with eighty-five medallions and plaques commemorating Dr. Franceschi, various historical events (fifteen of which are related to the American Revolution), and progressive luminaries.

[9][10] A duplicate (and today, a more well-preserved) set of the medallions were installed upon another house Freeman had constructed in 1931 that was named Casa Casuarina, otherwise known in more contemporary times as the Versace Mansion within the Miami Beach historic Art Deco district.

[10] In 1929, Freeman offered the property, including Montarioso, its rare plant collection, and some additional land just south of Mission Ridge Road to the City to serve as a park.

In 1968, the Santa Barbara Horticultural Society persuaded the City Council to hire a landscape architectural consultant to develop a master plan, which formally concluded a recommendation to demolish the house, as it “had little architectural merit and restoration would probably be impractical and very costly.” Although the City Council approved the master plan in 1971, the demolition was nevertheless opposed by Miss Pearl Chase, who formed the "Franceschi Mansion Restoration Committee".

Approximately ten of the total forty acres of the property was installed with numerous specimen plants that Dr. Franceschi had located in natural groupings to suit their ideal microclimate, soil quality, topographic elements, and sustainable water demands.

Partial sun plantings such as camellia, daphne, and rhododendron were cultivated under the shade of the California live oak trees (Quercus agrifolia), along with additional subtropical fruits, olives, palms, bamboo, and other vegetation in an attempt to yield flowering on the property year-round.

[6] First introduced to southern California by Dr. Franceschi in 1899 from specimens obtained from the Botanical Garden of Rome, the subsequently adapted lippia became popular within a dozen years throughout California and Arizona as a preeminent substitute for traditional grassy lawns, as it could thrive in virtually any quality of soil; required a tenth of the water as that of any other kind of lawn; could withstand temperature extremes; rapidly established itself even upon sloping topography whilst smothering out weeds; did not require mowing; and was not difficult to remove itself, because it had no underground runners.

[20] In 1963, Santa Barbara horticulturist Will Beittel conducted the first known survey of the horticultural specimens within the park and observed more than fifty remaining species of plants introduced by Dr. Franceschi were still growing onsite.

[3] Purportedly under financial constraints, the SCAA was incorporated in 1907 when Dr. Franceschi entered into an ill-fated partnership with Peter Riedel, a horticulturist and landscape architect from Holland who owned two nurseries in Montecito.

During this time they contracted design-build projects on a number of Santa Barbara estates, where large teams of workers would execute their plans that included planting their unique stock.