The €90m signing from Stuttgart has made an almost impact with the Magpies.
And Howe said: "Considering the short training time we've had with him, I think he's done really well and tried to implement our instructions as best he could.
"But we need to demand more from him, and we need more from him in the sense that he's the focal point of the team."
After 14 competitive matches, Woltemade has scored six goals, in addition to four goals for the German national team.
Howe is pleased with this record: "As far as goals are concerned, he's had a very good start. I think the goals he's scored during the international break will also do him a lot of good.
"Confidence is absolutely essential for a center forward, so I think he can be really satisfied with himself."