Google have a free speed checker for your site which you can check how fast it is on a desktop and mobile platform. This is a great way to try speed up your site. You may be able to do some yourself.

This is important for your site as the faster your site is, the better Google will view it. Google will then place your website higher than a not so fast website in the search results. The faster a website loads, the better a users experience is, and so where two sites offer equally relative content, Google will always place the better performing site above the slower one.

You can check how your site currently scores usingGoogle's free tool: https://developers.google.com/speed/pagespeed/insights/