Excellent interpretive trail.
Exit I-394 at Penn Ave. and follow the south frontage road (Wayzata Blvd.). Turn left at the first stop sign (a three-way stop), follow curve up to the right to a stop. Turn right onto the Wirth Parkway connection, then drive north on Wirth Parkway 1/2 mile to the driveway entrance to the Garden.
http://www.tripleblaze.com/trail.php?c=3&i=7627