Three? Four? Five? Six? The more the better and more traffic? Yes?...
NO!
Results from split tests by the Search Engine Journal say that using more than two or three hashtags led to significant drop in traffic. The maximum engagement was with just one hashtag!
So, the best course of action is to be a miser and don't go about spraying hashtags with the hope of more visitors.
Happy blogging. :)
(I have purchased all the images and I have the rights to use them commercially. Photo source: https://getstencil.com/?tap_a=9103-1801f8&tap_s=200974-3b53a9 )