You can custom php.ini just add environment PHPRC in your virtualhost.
fastcgi.server = ( ".php" => ((
"bin-path" => "/usr/bin/php-cgi",
"socket" => "/tmp/php.socket",
"bin-environment" => (
"PHP_FCGI_CHILDREN" => "3",
"PHP_FCGI_MAX_REQUESTS" => "1000",
"PHPRC" => "/usr/www/vhost1/php.ini"
),
"bin-copy-environment" => (
"PATH", "SHELL", "USER"
),
"broken-scriptfilename" => "enable"
)))