Diageo is adding blueberry to its high-flying range of flavoured Smirnoff vodkas.

Smirnoff Blueberry will hit selected retailers this month before rolling out nationwide later in the year, and join the Lime and Green Apple varieties that have recorded sales in excess of £5m since their launch last June.

A Diageo spokesman predicted the new flavour would gain sales momentum as the weather warms and would tap into the growing trend of at-home cocktail making.

"As with Smirnoff Lime and Smirnoff Green Apple, the key to unlocking the potential for Smirnoff Blueberry is for consumers to enjoy it as a long mixed drink," he said, adding that lemonade was the ideal mixer.

The drinks giant this week announced a further £2.15m marketing investment for the range over the next six months, building on the £3.65m it has spent since launch. The extra cash will be used to educate consumers on how to drink vodka as a long mixed serve.

Brand manager Jo Peat claimed many consumers were unsure which drinks to mix with flavoured vodka. An in-store sampling campaign is currently running through stores across the UK to provide drinkers with more ideas.

"The flavours should be merchandised alongside the standard Smirnoff vodka range," she said. "We recommend that retailers utilise display solutions and train their staff to highlight the perfect, long mixed serve to shoppers."