Wilshere has not played for Arsenal in over a year after he suffered an ankle injury, and despite Wilshere nearing a return, Wenger has admitted that he will not rush the midfielder's comeback.
Wenger told reporters: "October will be an important month for Jack. I will promise you that I will be careful, but Jack works very hard.
"Every day he is in early, late going home, is focused and has built up a good basis for his body.
"After how quick he will be sharp again for competition, I don't know. We will have to wait for at least a month to see that."
The 20-year-old has scored three goals in 64 appearances for Arsenal.