FTP sends all data, including credentials over cleartext. It's a *bad* idea to use it. I could enumerate the reasons why here, but instead, I'll refer to you to the always enlightening
http://mywiki.wooledge.org/FtpMustDie.
FTPS (FTP over SSL) is better, but if you're going to the trouble of setting that up, don't bother. Just use sftp, the server for which is already provided by your distro's ssh daemon. From the client's perspective, SFTP works in a nearly identical fashion to FTP, but it can take advantage of strong authentication (you do have password auth turned off, don't you?), as well as encryption all data including credentials.