Arsenal start their Champions League campaign on Tuesday at Montpellier, the club Giroud helped win the French title last season by finishing as the league's top scorer with 21 goals.
The France striker has not scored for Arsenal yet and started last weekend's match against Southampton on the bench, with Wenger preferring Gervinho in his attack.
Wenger refused to say if he would start Giroud at Montpellier but Gervinho's presence by his side for the news conference suggested that the Ivorian could be chosen again.
"The play is really different in England, especially for the forwards," Wenger told a news conference.
"Discovering the Premier League is always a shock because you have more collisions, more contacts. So it takes a bit longer for the forwards than the others to adapt to the English football. But I am a patient."
Wenger suggested that Giroud just needed one goal to get going.
"All forwards enjoy cycles. But sometimes, a goal is enough to trigger everything."
Montpellier centre-back Mapou Yanga-Mbiwa said Giroud would not find the net against his former club.
"For him, it would be great to shine in front of his former fans. But I already told him that, unfortunately, he would not score tomorrow," Yanga-Mbiwa said.
