Yes it is possible to do so by using certain berries.
You buy the berries in BW2 on Route 5 from a breeder. She'll give you 5 random berries daily.
Pomeg Berry -10 Hit Point EVs
Kelpsy Berry -10 Attack EVs
Qualot Berry -10 Defence EVs
Hondew Berry -10 Special Attack EVs
Grepa Berry -10 Special Defence EVs
Tamato Berry -10 Speed EVs
Source: http://www.serebii.net/games/evs.shtml
