add 30 days to date in php to mysql datetime code example
Example: php date + 30 days
echo date('d/m/Y',strtotime('+30 days',strtotime(str_replace('/', '-', '05/06/2016')))) . PHP_EOL;
echo date('d/m/Y',strtotime('+30 days',strtotime(str_replace('/', '-', '05/06/2016')))) . PHP_EOL;