I think I have some new favorite photos.
Situated on the other side of the tracks from the current campus of Hokkaido University, a surprisingly large botanical garden provided the environment for me to practice my macro photography skills, and when the sun finally poked its way through the clouds, I took some fantastic shots.
In addition to being a great place to take a stroll and take photos, there are several lawns and places to enjoy a picnic. The botanical garden is 10 minutes southwest on foot from Sapporo Station, and it's open 9:30-16:30 (until 16:00 October and November) from very late April to very early November. Admission is 400 yen. The greenhouse only is open the rest of the year with limited hours; admission during this time is 110 yen.
Note that the website (Japanese) for the gardens states the building with the preserved animals until this summer as it is earthquake-proofed.