I revisited Kew in April 2014.

My advice to first-time visitors is a) don't be put off by the airliners every 2 minutes - you'll get used to them: b) don't miss Kew Palace - it's tiny compared to WHS palaces like Versailles or Caserta but that's the point, George III lived frugally unlike autocratic monarchs elsewhere (Palace and kitchens now included in the entry price for the gardens); c) avoid the White Peaks café area - the historic Orangery does snacks as well as meals and is quiet and airy.

One of the big historic glass-houses - the Temperate House - is empty awaiting repairs to be completed 2018, but the other, the Palm House has been repaired and is open. The Pagoda may disappoint - there is no access and it lost its 80 gilded dragons long ago. The new Alpine House is a tiny gem and the Princess of Wales Conservatory should not be missed. Easily overlooked but one of my favourite buildings is the Marianne North Gallery built in C19 specifically to display the life work of a maiden lady who travelled the world painting plants and landscapes rather well.

Finally, of course the plants, trees and landscaping at Kew are wonderful - best to allow a whole day to see it all.