Just a quick note to other siteground users with ssh access to their shared hosting accounts: Drush can work via the command line in a siteground environment. Here are some specific settings that I had to include to get it to work:
alias drush='/usr/local/php52/bin/php-cli ~/drush/drush.php --php=/usr/local/php52/bin/php-cli'
You might want to check your particular shared hosting environment to ensure that the selected PHP version is not using fast-cgi, that seemed to cause problems for me with drush. Luckily, Siteground makes multiple versions of php available to its users. If you're having trouble, you can just take a look at the /usr/local directory and pick a different version of PHP