September 6, 2013 (La Mesa) – The City of La Mesa is holding its sixth annual “Sustain La Mesa” Environmental Festival September 7 from 10 a.m. to 3 p.m. at Harry Griffen Park, 9550 Milden Street, La Mesa.  The free event is presented by the La Mesa Environmental Sustainability Commission and will feature hydroponics, solar cooking, composting, electric vehicles, kid’s crafts and more.