For many traditionalists, the Chelsea Flower Show marks the ‘proper’ beginning of the season. This floral extravaganza is run by the Royal Horticultural Society, and usually attended on the first day by the Queen. It is phenomenally popular: numbers are now limited to 160,000 over the six days, and tickets are hard to get. However, one way is to become a member of the RHS, for whom tickets are reserved on Tuesday and Wednesday. At the close of the show, the exhibitors sell off their shrubs, trees and plants, as you can see by the human jungle making its way afterwards to Sloane Square tube station.

Dress code: Comfortably relaxed, with occasional hats, elegant dresses and linen suits/jackets on display.