You should not try to induce labor on your own before 40 weeks or without the assistance of a trained professional. Castor oil will not really induce labor- that's an old wives tale. It will however act as a laxative
Castor oil is very commonly used to induce the labor pains in post dated pregnancy. Castor oil stimulates the peristalsis and stimulates the uterus. It is a common experience to see the patient coming with labor pains very next day.
It MAY induce your labor.. old wives tale. I have never heard of anyone that it actually worked on but it WILL give you severe diarrhea! I would not try this one. Walking is the best thing to speed up your labor.