Poulters will work on campaigns based on calendar dates such as Mother's Day. It won the business following a competitive pitch against two undisclosed agencies.
Poulters joins roster incumbents Marketing Store and Inferno. Publicis Blueprint, which handles much of Asda's below-the-line marketing communications, will not be affected by the appointment.
Poulters has previously worked on a supermarket account, for Morrisons, but resigned the business in December 2003. The account was moved to BDH\TBWA.
Asda, the UK's second-biggest supermarket, is expected to expand its offering into new areas such as furniture this year.
The Wal-Mart-owned chain positions itself as a low-cost retailer; its chief executive, Andy Bond, has expressed a desire to widen the price gap between it and its rivals further.