In Polish it's Ogród (sing.) Saski.
Yes and as you previously pointed out the correct usage when translated is Saxon Garden. It doesn't suddenly become plural in English when referring to just one location.
The only time it would become plural is when referring to multiple gardens of the same style.
Here is an example:
"The garden next to the Royal Saxon Palace, which was opened to the residents of Warsaw in 1727 and named "Saxon Garden"...in the 19th century it became a model, a kind of public city park. This led to the establishment of other "Saxon Gardens" in other parts of the country, such as in Radom (1822/1824) and Lublin (1837)."copernico.eu/en/articles/capital-saxon-garden-baroque-vistula-river-warsaw-residence-city-saxon-electors-and-kings-poland
The Polish Tourism Organization (a Polish government website) also uses the proper singular form when publishing information in English:
"you can take a leisurely stroll through one of the large parks, like the Royal Łazienki Park or the Saxon Garden."pot.gov.pl/en/virtual-site-inspection/incentive-inspiration/warszawa/warsaw-essentials
The singular usage makes sense when considering that the garden was a singular feature of the former Saxon Palace.
Compare to Chatsworth House estate in the United Kingdom which has a garden and refers to it as simply as that and is singular.
About the garden"The 105 acre garden is the product of nearly 500 years of careful cultivation."chatsworth.org/visit-chatsworth/chatsworth-estate/garden/
But wait! What about Kew Gardens in London?
It's proper name is the Royal Botanical Gardens, Kew (the main location) with another location in Wakehurst, Surrey. The site in Kew also has several botanical structures dedicated to different types of gardens like bamboo, grasses and woodlands.
The whole point in translating one language to another is that the target language and the source language differ.
The whole point in translating is to be actuate and respect the source language.
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