All major improvements to rental property that become "a physical part of" the primary structure (including landscaping) are classified as Residential Rental Real Estate" and depreciated over 27.5 years. Since the land is not a depreciable asset, for landscaping improvements that would mean your "COST" and "COST OF LAND" would be identical, and nothing would be depreciated on that specific asset. But it would add to the cost basis as it should.
