While white HDPE (like milk bottles) is the most recycled plastic, there is much less demand for coloured HDPE because the coloured material is hard to sort. Even properly cleaned and placed in the blue bin, the chance of coloured HDPE being recycled is quite low. So if there is no recycling bin handy, do not feel bad about throwing away non-white HDPE. Or better yet, clean it and save it for a local recycling project as suggested above.