It is important to buy locally grown food to get the best quality, put money back into the regional economy and support farmers. All Whole Foods stores carry locally grown food; they even have signs that inform the consumer as to where it's from and if it's commercial or organic. Whole Foods also invites local farmers to their stores to do demonstrations. The Harvest Cooperative Market (in Cambridge and Jamaica Plain) also carries local produce. The Porter Square and Sidney Street Star Supermarkets have the largest selection of local produce. From June through October, local produce and fruit is also available at the 30 Middlesex Farmer's Markets across the state.