The organic (ecológico) farmers market in Plaça de Pep Ventura now also happens on the second Saturday morning of each month (in addition to the last Saturday). The prices are great and you get to buy directly from the farmers/producers.
There's also two good fruit stores nearby. One is near the end of Carrer de Castillejos (which sells delicious "mangas", which are like mangoes but more delicious) and the other on Carrer de Santa Anna.
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