Posh will play Leyton Orient in a two-legged semi-final with the prize of a promotion showdown at Wembley against either Preston or Rotherham in the final.
"Now it is all about the play-offs and I love being involved in them," said Ferguson following his side's goalless home draw against Port Vale.
"Orient are the best opponents we've faced at London Road all season and they deserved to win here, but we were just as impressive when getting a result at their place. They are going to be two huge games."
A much-changed Peterborough team finished the regular season with a stalemate.
Ferguson handed a debut to Portuguese defender Ricardo Santos, who arrived from non-league Thurrock in February. That was one of eight changes he made against Vale.
Another non-league acquisition, Kyle Vassell, failed to take the hosts' best chance.
Vassell was denied by the legs of Vale goalkeeper Sam Johnson on the half-hour after taking too long to get his shot away. He then turned provider when Josh McQuoid sent a snap-shot just over the crossbar on the stroke of half-time.
Vassell saw another effort deflected wide early in the second half before a third opportunity was snuffed out by a block.
Posh were much improved following a double substitution which saw Joe Newell and Danny Swanson arrive from the bench, but they could not manage a breakthrough.
Ferguson said: "I felt I picked a team that was more than capable of winning the game.
"We didn't play with anywhere enough energy in the first half, which is why I made changes at the break.
"We were much better in the second half when we performed in the way that people expect a Peterborough team to play. I felt we should have got three points, but it wasn't to be.