Meta Description for blog pages

Hi.

I'm having an issue getting blog posts to output and wanted to check I'm not missing something.

I've added this to my post.php file ;

<?php perch_blog_post_meta(perch_get('s')); ?>

and in the post_meta template, I've added;

<meta name="description" content="<perch:blog id="meta_description" label="Meta Description" type="textarea" size="xs" escape="true" />" />

I've then added some text to this field in the social and meta tab and saved, but this doesn't show in the post meta when viewing the page source.

My Diagnostics;

Perch: 2.8.26, PHP: 5.4.45, MySQL: 5.5.46, with MySQLi
Server OS: Linux, cgi-fcgi
Installed apps: content (2.8.26), assets (2.8.26), categories (2.8.26), perch_blog (5.0)
App runtimes: <?php $apps_list = array( 'content', 'categories', 'perch_blog', );
PERCH_LOGINPATH: /perch
PERCH_PATH: /home/genx/public_html/perch
PERCH_CORE: /home/genx/public_html/perch/core
PERCH_RESFILEPATH: /home/genx/public_html/perch/resources
Image manipulation: GD
PHP limits: Max upload 5M, Max POST 128M, Memory: 128M, Total max file upload: 5M
F1: 2edba60ed1f613d6dd804feb202456a2
Resource folder writeable: Yes
DOCUMENT_ROOT: /home/genx/public_html
HTTP_HOST: genx.media
REQUEST_URI: /perch/core/settings/diagnostics/
SCRIPT_NAME: /perch/core/settings/diagnostics/index.php