How encrypted root partition is mounted on boot?

What are the chain of processes that are implemented on boot when the root partition is luks encrypted? I installed Linux Lite on two manually created partitions - boot (unencrypted), and root (encrypted), but on boot after the grub screen instead of prompt me to enter the luks password for the root partition i get initramfs prompt shell.

I am trying to find what is the problem. I mounted the root partition from live use and checked /etc/crypttab and the file was empty, so my guess is that the installer didn't do something right during the installation.