The Holbrook Farmers Market is open for the season. Two farms, Holbrook Farm and Earthwright Farm, are offering such crops as herbs, lettuce, radishes, and peas, plus vegetable plants for the home garden. As the season continues, the market expects to have more vendors and a wider variety of vegetables, including beans, bok choy, broccoli, squash, and tomatoes, according to market manager Susan Wright, co-owner of Earthwright Farm. A maker of organic nutritional supplements plans to join the market soon, and Wright is trying to finalize arrangements with an owner of miniature horses to offer rides to young children. “We like helping people get food that they can be secure about where it’s coming from,” she said. “Nowadays, you never know what’s been done to your food.” The market, located in the parking lot of Union Street Lanes at 231 Union St., runs from 10 a.m. to 2 p.m. Saturdays into October.