In North America, we certainly have no Sissinghurst or Stowe, and relatively few gardens notable enough to give great concern about how they will survive after the passing of their owners. Nevertheless, consideration of the challenges presented by such gardens can reveal much about what is of value, and worth preserving, in a garden, even a new one, and what isn't.
Gardens Illustrated has made available a new podcast of a talk by Sir Roy Strong, former director of the Victoria and Albert Museum, and Fergus Garrett of Great Dixter. Here is GI's summary: "Sir Roy Strong, who created his garden The Laskett together with his late wife, and Fergus Garrett, head gardener at Great Dixter in Sussex (home to the late Christopher Lloyd) talk about their experiences of gardening with a legacy. They consider whether a garden can be expected to live beyond the life of its owner, and how to move a garden forward while respecting its heritage."
To download the podcast, go directly to the GI website. This podcast is near the bottom of the page.