Jaramillo's story as a curandero begins when he was suffering from a nose ailment and as a cure, daubed his nose with mud at the edge of a pool. Three days of this self-prescribed treatment cured the ailment, however, it left Jaramillo with an identifying scar on his nose. On the third night of this treatment, Jaramillo believes he heard a voice telling him God had given him the power to heal. Testing such power, he prescribed a tepid bath to his master which healed his ailment.
The first accounts of his cures and powers were collected and printed in 1934 in Spanish, they were later in 1951 translated to English. There is a shrine in Falfurrias at his burial site.
In many of Jaramillo's treatments, the number nine plays a prominent role, such as prescribing treatments often for nine consecutive nights, or in quantities of nine. The tales of such treatments include stories of people who did not follow his instructions or changed his prescription and failed to recover, leaving only those who followed his treatments exactly as prescribed as achieving complete recovery. Jaramillo's cures were often miraculous in nature, even to the point of curing paralysis.
Water has also been identified as a central theme in Jaramillo's cures, often requiring the ailing person to drink water for a specified length of time, or bathing in the water a certain number of days.
Some of the tales portray Pedro Jaramillo as a clairvoyant. He would know inherently if someone was lying about an illness or ailment. In one story he knew of a conversation that took place without him present. In Mexican culture, Jaramillo is displayed prominently in adorning homes in the form of paintings and statues.