The British Heart Foundation's shops division has launched its biggest ever appeal for stock after donations fell by 20 per cent.
The charity aims to raise 350,000 bags of donations by the end of September through its Big Donation appeal. It estimates these will be worth about £7m.
A spokeswoman for the charity said its shops were particularly busy because of the recession, so it needed to increase its supply to meet demand.
The BHF is working with retailers Argos, Homebase and Lidl, which have set up drop points at stores where people can donate unwanted goods to the charity.
It will also run a PR campaign to raise awareness of its need for donations.
Diane Locke, chief executive of the charity's shops division, said: "Stock is the lifeblood of our shops. This is the biggest campaign BHF Shops has launched, and we're appealing to everyone across the country to get involved."