The hallmark of a great garden is to be able to see it at any time of year and come away impressed. I've just spent time at Great Dixter on a Gardens Illustrated day on 'Choosing and Using Good Plants' with Fergus Garrett.
Although officially closed for the winter now, the garden was still looking sumptuous and Fergus's talk (together with his almost 400 slides!) was inspiring. Worth the awfully long drive to get there and back in a day. I would never want to replicate GD's high-maintenance and high density plantings but I came away in awe of Fergus's plant knowledge determined never to accept anything but the best and most interesting 'forms' again.