description showing before enclosing tag

<?php
			global $post; // if outside the loop
			if ( is_front_page() ) {
		    // This is the homepage
				echo '<h2 class="tagline">'.bloginfo('description').'</h2>';
			} else {
		    // This is a subpage
				echo '<p class="tagline">'.bloginfo('description').'</p>';
			}
		?>

I’m using this code in my header.php to show the blog description. The PHP basically puts the description in an h2 tag on the homepage and a p tag on subpages, for SEO. However, for some reason the actual description comes before the tag in the source.. I can’t figure out why. For example:

This is my description<h2 class="tagline"></h2>