The studio at Charleston in Firle was built in 1925 by Vanessa Bell, Duncan Grant and Roger Fry.
The exhibition will feature many pieces loaned from Charleston, the Bloomsbury set's Sussex home.
South East Coast Ambulance Service says rescuers are able to use the app to locate those in need.
Figures show food production provides 45,500 jobs and £813m to the South East and London economy.
The painting, by Duncan Grant, was at risk of being auctioned and being taken away from Charleston.
Sir Lenny Henry will also attend the festival, which takes place at Firle, East Sussex, in May.
The A27 project east of Lewes creates nine miles of shared-use pathway for cyclists and walkers.
Sara Thornton strolls along the South Downs Way, which stretches from Eastbourne to Winchester.
