There is no dress code, though Zen Buddhists generally like the environment to express a sense of integration, with its different elements unified harmoniously. It's a teaching point, really, about mindfulness to the integrity of our experience as living beings. So, best to wear earthy colors that reflect those of the Temple's interior space. But this is nothing anyone is crazy serious about: if you show up in a bright red Metallica t-shirt and lime green sneakers, you'll be more than welcome.
I'm one of the Dharma teachers at Zen Buddhist Temple. We suggest people wear clothing that is not too bright or distracting when attending our public services, but that is not required. Also, it's helpful to wear clothing that is loose fitting for your own comfort during meditation sitting.
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