Hi RunEveryStreet, the landuse key has a pretty strict set of values, although there might be cases where a user-defined / undocumented value is the best fit.

In this case, we already have leisure=garden, so it isn't necessary to define the feature further with a landuse tag. However it's clear the tag is intending to specify the type of garden feature present here, which can be tagged with the garden:type key

https://wiki.openstreetmap.org/wiki/Key%3Agarden%3Atype

One of these values is garden:type=rock_garden . If you're familiar with this site, would you agree that this would be a better way of defining the way?

Although it might seem obscure, if someone really wanted to see a rock garden in north wales, or wanted to see how many rock gardens are in the UK, tagging the way this way would be useful :)