Both players have been handed new contracts at Villa Park after impressing last season, and Lambert has called on them to further improve during the next campaign.
The 43-year-old told the Express and Star: "They will have so many ups and downs like everyone else. They have got to kick on again. There is no point in doing it for one year, and then resting.
"You have to go again then again, and every year you have to step up to the plate and this year will be no different.
"The lads have done great but you have to kick on again and not rest on it. They are young enough lads, they have got so many years ahead of them."
Baker made 30 appearances for Villa last season, while Austrian striker Weimann netted 12 goals in 39 games.