This topic might be better suited for landscaping forum maybe, but figured majority readers come here.
Re-reading 1949 Instructions for assembling and operating Lionel trains, a page entitled how landscaping will make your layout more realistic. Landscapes made of natural and green dyed sawdust sprinkled over water glass solution (?). Shrubbery is Norwegian Lichen (no details that it is to be soaked in glycerin to prevent dry outs). Rivers are blue construction paper with painted white streaks. Bridge pilings made from wood blocks . Roadways made with crushed stone, fine gravel, or dried coffee grounds spread over sodium silicate (?) to anchor it (imagine that getting into motors and bearings). You could paint background hills, buildings and clouds for perspectives.
So if you grouse some over expensive shrubbery, trees, landscaping materials, ready built buildings, or real photo backgrounds, think how much more fun it was back in those good old days!!