Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Phoenix Sky Harbor Intl Airport to Mallorca as you normally would.
Due to multiple factors, expect to potentially pay more when booking in March. For low rates, October can be a great choice for travel to Mallorca. Flights to Mallorca from Phoenix Sky Harbor Intl Airport in October are about $1,031 on average during October, but can be found for as low as $596.