The garden belongs to the neighbour (singular) so needs an apostrophe before the "s".

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Nor did Marc Maria object when denied an apostrophe for "Patriot's Peak, " a nubble he owns in Maine.

WSJ: In U.S., Apostrophes in Place Names Are Practically Against the Law

People here long identified a peak with the old settler, James Cameron, and spelled its name with an apostrophe.

WSJ: In U.S., Apostrophes in Place Names Are Practically Against the Law

An apostrophe, the argument goes, implies private ownership of a public place.

WSJ: In U.S., Apostrophes in Place Names Are Practically Against the Law

He is also a Hawaiian kid with an apostrophe in his surname.

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In Newton Abbot, residents of Bakers Views - named after writer and explorer Sir Samuel White Baker - have differing opinions over whether their street sign should have an apostrophe.

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"The apostrophe has a function, " says Thomas Gasque, an English professor who spent years on South Dakota's Geographic Names Authority.

WSJ: In U.S., Apostrophes in Place Names Are Practically Against the Law