It does vary from area to area, but in the Campo you will definately need a Licence, if you enquire at the Ayuntamiento they will tell you when and where you can obtain the licence, you will need a copy of your escritura (copia simple) to show where your land is ( when you go to apply), there will also be strict guidelines as to when you can light your fire, and what precautions you have to take.
I don't know your particular area, but where I am, if it is within the confines of a garden as opposed to campo, you do not need a licence, but the fire has to remain small, and has to be extinguished totally by 2pm and can only be lit, Monday to Friday, attended at all times, and a hosepipe on standby. All sensible precautions.