Do you know if they have wheelchairs - electric scooters that can be borrowed? And is it in a lot of direct sun outdoors or are there places to sit down for breaks in the shade?

Didn't see any wheelchairs or scooters for loan. There are lots of shady spots and lots of sunny spots. It's got plenty of wooded areas, some of which are loaded with sculptures. I've seen plenty of people picnicking in shady spots as well as sunny spots. Much of the sculpture park is wheelchair accessible, but parts of it are difficult.

There there are no wheelchairs or electric scooters, but there are a lot of places to sit down and there is a lot of shade.

Agreed. I've never seen wheelchair or scooter loaners. You could reach out to The Trustees and suggest that. Lots of shady spots, but the museum and park are on the side of a hill