Here are some reasons for the slowness of your site.
1)Eliminate render-blocking JavaScript and CSS in above-the-fold content
Your page has 8 blocking script resources and 13 blocking CSS resources. This causes a delay in rendering your page. None of the above-the-fold content on your page could be rendered without waiting for the following resources to load. Try to defer or asynchronously load blocking resources, or inline the critical portions of those resources directly in the HTML.
2)Reduce server response time
Your server responded in 4.5 seconds. There are many factors that can slow down your server response time.
3)Leverage browser caching
Setting an expiry date or a maximum age in the HTTP headers for static resources instructs the browser to load previously downloaded resources from local disk rather than over the network.
Full Details