In Mervyn Miller's Raymond Unwin: Garden Cities and Town Planning the story of Jardim America is detailed in one paragraph:
In 1916, Unwin was commissioned to provide a layout for Jardim-America (sic) a garden suburb to the west of the rapidly expanding Brazillian provincial capital, Sao Paulo. Its Director of Public Works, Dr Victor da Silva Freire, had visited Letchworth and Hampstead. The City Improvement and Freehold Land Company had acquired a 240-acre [96 hectare] site adjoining the grid layout of an earlier town extensions. The requirement for 50 ft (15 m) streets ruled out the visual intimacy of Letchworth and Hampstead. Unwin added diagonals and a few curved streets to break the grid. He widened the central Avenida Brazil to form a boulevard, crossing diagonals in a central hexagonal circus recalling Sollershott and Crickmer Circuses at Letchworth and Hampstead. Subsidiary curve streets helped to minimise traffic short-cuts. Block centres included open spaces. The development included very low-density, largely detached houses on generous plots. Unwin was unable to travel to Brazil but, in January 1917, Barry Parker arrived for a two-year sojourn, during which period he developed the layout, designed many individual houses and fave advice on the planned extensions of Sao Paulo and other Brazillian cities. (Miller, Raymond Unwin, Leicester UP, Leicester, 1992 p. 154)
Recently I purchased a copy of Silvia Ferreira and Santos Wolff's Jardim América, a history of the suburb. It's in Portuguese, another language I don't speak, but (with the caveat that of course if you don't speak the language you're translating out of, you can't necessarily really know the truth of these things) google translate does seem to be getting better and better all the time, so I have typed in the elements pertaining to the 'jardins internos'.
Google-translated to English, p. 133 of the book tells us this:
'Barry Parker traces his suburb of houses within this trapezoidal shape. He articulated a plot, in the most Cartesian origin, with an organic system of diagonal and curved streets and with blocks of varying sizes and shapes, all interspersed with extensive portions of green and landscaped areas, with the vast majority of the blocks still having internal gardens. These semi-plush gardens, species of parks, gave a distinctive mark to Jardim América. They were spaces that created green areas shared by the residents and that sought to apply the concepts related to the uses of the private and segregated gardens of each case.'
It won't surprise anyone to hear that picking through a book written in a language one doesn't know, and which is not indexed, to find mention of one feature amongst many, is not an easy task. I am heartened though that the authors are clearly very attuned to the importance of the internal reserves in the Jardim América design. This is true not least when they detail the demise of the reserves - and they are, now, all gone. This chapter, once again google translated so all care, no responsibility (and, I hope, not a copyright infringement) gives the story of their removal/redevelopment in detail I have not seen in any other similar 'garden suburb' history account:
'The occupation - successive changes
'It can be considered that the occupation of Jardim América took place between 1913 - the time of the first milling and drainage works in the torrenos - and 1958 - when the last approval by the City of a new house project on land not previously occupied takes place. A very long period. In 1916 the first house of the subdivision was built and in the following year Barry Parker began to design residences in City lots. The implementation of the neighborhood, however, can have its periodization quite reduced: from 1919, when sales of lots and construction of houses started to occur at a more effective pace, until the mid-1940s, after which they were not approved. More than twenty new projects. Within this period, the pace of occupation followed the offer of land presented to the market.
'The occupation of Jardim Amērica suffers from sales inflows according to the changes in the subdivision. In the first gloss, more than half of the available lots are sold, generally those located in the center of the neighborhood, next to the main arteries. In the following period, the "peripheral" plots are almost entirely acquired with the exception of the enlarged part and the extension then opened on Rua Bolivia in the years 26/1930, the neighborhood is practically occupied.
'However, the shredding of the internal gardens carried out between 1931 and 1935 will create the availability of a large number of new lots for sale, easily absorbed by the market. The last redefinition of the places on the old Chile street will cause the blocks to be relocated by this new route. The relocation of this sector of the neighborhood causes the appearance of a greater number of lots, with the entire Jardim América occupied until 1945.
'The first phase described corresponds to the occupation of the neighborhood driven by the success of the initial sales that led to revisions of the original project in search of a greater number of lots. After the expansion obtained with land purchases, it was found that it was impossible to expand the neighborhood due to the limits of its perimeter. Jardim América then "grew inwards" with the subdivision of previously demarcated areas and those destined for purposes other than individual plots.
'The first expansion took place almost concurrently with its launch, during Barry Parker's stay in the city. In fact, what the architect himself drew was an application, already mentioned, on the right side of the neighborhood. A new street was created, Chile (now Nine de Julho), largely parallel to Canada Street and forming a "U" with it, through a curved connection of its lower extremities. With this change, Praça América started to constitute a kind of geometric center of the neighborhood. In addition, at that time, some lots were also acquired and incorporated into the sales map on United States Street, on the outside of the original perimeter.
'After such a simple expansion operation, the process of reviewing the internal areas of the subdivision began, creating new lots, without buying more land. With different justifications and through changes in the original design, City increased the number of lots for sale whenever it could.
'Due to the irregular design of the courts, the shape and size of the lots varied a lot since the beginning in Jardim América. But in the beginning, most of the lots were characterized by their large dimensions, with fronts of at least 20 meters and areas rarely less than 900 square meters. The new sectors, the object of changes in the general design, progressively decreased the size of the land, reaching lots of 450 and even 360 square meters in the last subdivisions, which also contributed to increase the number of units for sale.
'The alteration that most changed the original spirit of the project and that increased the stock of land for sale in Jardim América was the eradication of the internal gardens of the courts and the subsequent sale of these areas.
'The first change in this direction took place in the late 1920s and took place through the division of a large block, not yet commercialized, into two smaller blocks, creating the extension of a street, Bolivia, between Argentina and Canada. For this operation, the internal garden of block 41 was destroyed and each block resulting from the division started to have a small internal garden, also eliminated in another later reform. The difference is that the area now has 33 lots, instead of 23, a considerable gain for the sales policy.
'The next step in this process of increasing available land occurred with the installment plan and the sale of the remaining internal gardens. This resulted from a long battle to define the responsibilities for the conservation of these gardens. The owners of the lots adjacent to them exempt themselves from the costs and maintenance, since if the gardens were opened to the public through alleys, they argued that they should not be responsible for the care of the areas.
'It has to be reflected that, like the American suburbs without fences, semi-private or private gardens but somehow open to the public space constituted urbanistic patterns and of relationship with the city imported from different cultural and urban traditions. The landscaped spaces whose fleet and property limits were not well defined did not find resonance in the Brazilian way of life. Although the internal gardens were initially attractive, there was no one who assumed the preservation of a space that was not entirely collective, but that was also not private. The grounds of the internal gardens were only effectively taken over when fenced, walled, delimited, privatized, an attitude that, in general, still remains in Brazil in community areas belonging to private subdivisions.
'The idea of subdividing the semi-public internal gardens was realized in stages. Many owners of plots that could face the street were sold at normal prices, but the solution that most reflected in the density of the neighborhood was relocation, through the creation of new streets.
'An entire block that had not been sold on the far right of the neighborhood was subdivided into four blocks of small lots, with the creation of the streets Cuba, Martinique and Espéria. And four streets in cul-de-sac, Guayaquil, Lucatā, Puerto Rico and Newfoundland led to the creation and sale of more than fifty new lots around 1935. The fact is that the Jardim América subdivision, started in 1919 with 396 lots for sale, due to the expansion or internal subdivisions of its area, ended the commercialization with 672 plots.
'Taking into account that the increase in area in relation to the original external perimeter was not very significant, what is noticeable is that the enthusiasm that Barry Parker had with regard to the potential of sale of the neighborhood had not been unfounded. The architect did not anticipate, however, that with the possibility of more profit the company would partially de-characterize its original design.'