It depends on the severity.
In general grade 1 strains usually recover in under 3 weeks. Grade 2 strains/tears - 4 to 6 weeks. Grade 3 tears - 8 to 12 weeks. Typically surgery is not recommended and recovery involves rest, stretching, and controlled strengthening. However, if 2 of the 3 tendons are avulsed from the origin, early surgery to repair the tendon to the origin would be an option.