The campaign will hit 100 Sainsbury and Tesco stores throughout June and July with posters and pop-up displays in foyers and beers, wines and spirits aisles to support the activity, which promotes the drink as an icon of the British summer.
A team of 32 Loewybe brand ambassadors will be on hand at stores around the country to educate consumers about the drink.
Louise Dyer, personnel director at Loewybe, said: "We've built in an element of planned flexibility into this campaign, and are combining our experiential and traditional field marketing skills to deliver for the brand."
Loewybe has been working with Diageo for six months on a variety of on-trade field marketing activity for a range of brands.
The Pimm's campaign is the first consumer-facing campaign the agency has been briefed to work on.
Diageo has recently launched a 拢4m multimedia campaign, created by Mother, tying the drink with summer barbecues, comprising TV, radio and online activity.
The brand is also launching a book this month called 'Burnt Sausages and perfect Pimms', with celebrity endorsement from actress Maureen Lipman, chef John Torode, and ex-BBC News royal correspondent Jenny Bond.
Pimms is also planning to introduce a one-litre premix bottle as well as an expansion of the draught Pimms variant that was trialled last year in 350 pubs and bars around the country.
Loewyby, which celebrates its 20th birthday this year, was formerly called MHP, but relaunched as Loewybe two years ago.
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