As a botanical garden, this place was quite lovely, but the main reason we stopped was because it was the last day of the Mosaicultures Internationalle and it didn't disappoint. Just check out the last page and change of the photos and you'll see why we decided that this was a must visit location when in town. I'm sure it's quite lovely all year round, but the topiary work that was on display was exceptionally innovative.
And also note that admission purchased on-line was substantially less expensive than at the gate. You also get instant entry with a printed or digital display of the PDF ticket receipt.