Joao Moutinho's 61st-minute goal was all that separated the teams in their UEFA Champions League clash.
Jardim hailed the win as vital, particularly given Monaco have made a poor start to their Ligue 1 campaign.
"It was important to win for various reasons – to give confidence to my players, to show that our work can be rewarded and that we are progressing," he said.
"Our physical conditioning is at a high level and we showed it in the second half. We were superior to our opponents."
Jardim was impressed by his side's second half, when Moutinho's goal came after Dimitar Berbatov's headed pass.
He also praised Portuguese substitute Bernardo Silva, who was introduced four minutes before the goal.
"I told them to pass the ball quickly and put pressure on our opponents, which they did very well," Jardim said.
"I think that Bernardo Silva's introduction was an asset for us. My team played better in second half. We had the ball more and our opponents were not as well balanced."
