are there she orcs??

[The Saucepan Man]

You think it might take Saruman awhile to wait for thousands & thousands of Uruk-Hai babies to grow up to, even say 20, until he warred against Rohan?

According to the Tale of Years in the Appendices, Saruman withdrew to Isengard and fortified it in TA 2953. At the same time, he started setting spies on Gandalf and began keeping agents in Bree and the Southfarthing. He first used the Palantir of Orthanc, and became ensnared by Sauron, in about TA 3000. Even if you take the later date (which is the more likely), that's sufficient time to enlist Orcs to his service and to breed more for an army. I'm sure that Orcs were old enough to fight by 18.