Some of my favourite gardens from the first episode included those of Luis Barragan in Mexico.
The most human of all arts because we inhabit them.
Casa Barragan. Photo from here.
Also the wonderfully whimsical and fantastical garden of Los Pozas in Xilitla by Edward James between the 1940s and the 1980s. It reminded me of the Sacro Bosco, at Bomarzo, Italy.
Photos from here.
Sacro Bosco, Bomarzo, Italy.