Writing an article and ranking a page are two separate things entirely.
You can have the most well written, best quality, most resourceful article on the planet, but if it's placed on a site with low authority you're going to have to put in the groundwork to get it ranking.
If your website already has authority, all new blog posts can piggyback off that and rank well without much promotion, assuming your site interlinking is done properly (contextual interlinking is more powerful than nav, sidebar and footer links).
If your website is fairly new you'll have to do some link building to the article to give it a boost in the SERPS.
You can do this utilizing your social media accounts. Share, Tweet, G+ and Pin your article, encourage others to re-share/tweet/pin etc.
Don't forget each share on a social network adds another backlink to your website (aka social signal)
Make sure you have social sharing elements clearly visible on the page, and don't forget to actually ask your readers to share your content within the article.
Along with having a solid content marketing strategy, don't forget to also constantly pursue strong backlinks to increase your overall site authority, this will help future content rank faster with less promotion.
Building strong links to your homepage and inner pages strengthens not only the pages the links are pointing to, but also the other inner pages which they link to.
Link juice flows throughout the whole of your website, increasing the ranking potential of all pages.
