Many places that usually charge for entry or are closed to the public are offering free admission, to give as many people as possible the chance to visit them and be inspired.
The Royal Horticultural Society is taking part, opening its four beautiful gardens - Wisley in Surrey, Hyde Hall in Essex, Rosemoor in North Devon and Harlow Carr in North Yorkshire. Some RHS partner gardens, National Gardens Scheme gardens and others are also opening free on that day. Details at: http://www.nationalgardeningweek.org.uk/National-Open-Gardens-Day;-17-April.aspx
It's all part of National Gardening Week (April 13 - 19). Launched four years ago by the RHS, it has since grown into the country's biggest celebration of gardening. For details of the talks, walks and places to visit see http://www.nationalgardeningweek.org.uk/