Yes, you can use FTP over SSL.
You can also use DriveHQ FileManager and / or DriveHQ.com and turn on the SSL feature. DriveHQ FileManager supports HTTPS/SSL.
There is even more secure solution if you use DriveHQ FileManager or DriveHQ Online Backup. Both client programs support HTTPS and encrypted folder. HTTPS makes it very secure for data transmission; encrypted folder makes it more secure as your files are encrypted locally before they are uploaded; your files will remain encrypted on DriveHQ server. Further, the encryption key / decryption key is never sent to DriveHQ server.