Looking at the timing of just social and blog marketing may still leave you out to pasture with some folks unless email timing is factored in.
Most social networks and even your blog can send an email notification to your readers/followers. When will they be most likely to open and click the link to your post? This email timing infographic from KissMetrics.com will set your time straight.
If you automate your blog and social posts, careful thought should be given to your post timing for social, blog and email to optimise one or balance them all for best results.