The husband-and-wife team initially operated as Carver Knowles (NW) Limited before becoming Rostons.
Ros said: “To mark this momentous occasion, we are planning some small events – the first of which will be at the Nantwich Show.
“Clients and friends are welcome to join us from 2.30 pm for jelly and ice cream as well as our usual hospitality. We look forward to seeing you there!”
Refreshments will be available on a first come first serve basis.