Spain does fresh produce remarkably well - and that includes the fruit and vegetables that are so important for vegetarian and vegan diets. Spaniards have a great respect for what's in season, with market sellers and greengrocers often only selling produce from within Spain.
If you are in Andalucia more permanently and have a kitchen to cook in, then keeping to your vegetarian diet will be much easier. Supermarkets such as Mercadona, Mas and Super Sol don’t have a huge variety of wholefoods and veggie-friendly ingredients. However, most stores stock a good selection of grains, pulses and cheese as well as soya.
Trying to order a vegetarian meal in a Spanish restaurant can be a challenge - just explaining to your bemused waiter you don’t want any dishes containing meat or fish can be problematical. Some good phrases to learn are: No como ni carne ni pescado (I don’t eat meat or fish), and ¿Esto lleva carne o pescado? (Does this have meat or fish in it?).
Spain used to be a vegetarian's nightmare with all those hanging hams and meaty tapas. Vegetarians had no option but to constantly opt for ensaladilla Rusa (the Russan-Spanish potato salad usually served as a tapa), tortilla (Spanish omelette), or the famous main course of huevos con patatas fritos (egg and chips), with the occasional greasy green pepper on the side.