ftp uses unencrypted passwords so anyone can intercept your password without much effort. Therefore use curlftpfs in combination with SSL certificates if your are not mounting some local LAN ftp server.
On Debian you can mount ftp using curlftpfs as a root and this allows only root user to access ftp mount. No other users are allowed since by default only users that mounts has and access to mount directory. When mounting ftp as a non-root user you may get a following error message:
fuse: failed to open /dev/fuse: Permission denied
Rather that changing permissions of /dev/fuse you can allow other users to access ftp mount directory with an curlftpfs's option allow_other. The command will look similar to the one below: