Wilshere will be reintegrated into the first team slowly, with a run-out for the reserves likely in 10 days' time.
"We will see how he responds to the training now," said Wenger, who takes his side to Barclays Premier League champions Manchester City on Sunday.
"We will have to be a bit patient, a bit cautious, because when a guy has been out or 14 months it takes a while to get back to match fitness.
"Jack is fit to practice and play, but to put high-level performances in takes time.
"He will need a few games in the reserves."