The Duke of Edinburgh, the Prince of Wales, the Duchess of Cornwall, the Duke of York and Princess Beatrice will all be in attendance to preview the five-day festival, the most famous flower show in the UK.
Among those awaiting the royal visit will be Prince Harry, who will show his grandmother around a garden created by his Lesotho-based charity Sentebale.
Also attending before the flower show is open to the general public at the Royal Hospital Chelsea in west London are Helen Mirren, Joanna Lumley and Jamie Oliver.
