Coming from someone who has English as third language, I'd say you're fine without, since all documentation is available in English and most discussion is going on in English. I have actually never used my first or second language for participating in software community discussion. OTOH, these are minor languages with 6-10 million speakers worldwide, all of which learn English in school anyway.
However, among the worlds greater languages, there are certainly a lot of people who can't communicate well in English and there is a lot of discussion in these languages. So I would say, pick one major language that could be useful in all walks of life. Or just pick any language that you are interested in. However, for the sole purpose of participating in the programming community, I don't think time invested will pay off.
There are two crucial reasons for learning a language: necessity and personal motivation. If it isn't necessary for you, you'll have to go with motivation. So, pick a language that you want to learn, because you want to learn it.