From Yokohama Station: You can take the municipal bus number 8 or 148 and get off at the "Sankeien-Iriguchi" stop. The ride takes about 35 minutes.
From Sakuragicho Station: Take bus number 58 or 99 and alight at the "Honmoku" stop, from where it's a 10-minute walk to the garden.
Negishi Line: If you are traveling by train, get off at Negishi Station, and from there you can catch the number 58, 99, 101, 108, or 126 bus to the "Honmoku" stop.