PATH not getting exported from ~/.profile until manually sourced

Question

I am trying to modify my PATH in ~/.profile:

export PATH=$PATH:/opt/jdk1.8/bin
echo "Path is exported."

I will always login via SSH so that's why I have it in ~/.profile. I am using zsh (oh-my-zsh) as my default shell and in my ~/.zprofile I am sourcing ~/.profile:

source ~/.profile

The weird part is that when I login over SSH, I see the "Path is exported." message which means that the source statement .zprofile is working but when I echo my $PATH the '/opt/jdk1.8/bin' is missing. If I then manually source ~/.profile, the path is updated properly so I am not sure why it doesn't export the path properly when it gets sourced on login. This is all inside a vagrant box if that helps. Any ideas?

Edit: Output of zsh -ixc exit 2>&1 | grep PATH:

+/home/vagrant/.zcompdump:1254> _postpatcomps=( '(p[bgpn]m*|*top[bgpn]m)' _pbm '(texi(2*|ndex))' _texi '(tiff*|*2tiff|pal2rgb)' _tiff '-value-,(ftp|http(|s))_proxy,-default-' _urls '-value-,LC_*,-default-' _locales '-value-,*path,-default-'
_directories '-value-,*PATH,-default-' _dir_list '-value-,RUBY(LIB|OPT|PATH),-default-' _ruby '*/X11(|R<4->)/*'
_x_arguments 'yodl(|2*)' _yodl )
+/home/vagrant/.zshrc:56> export 'PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games'
+/home/vagrant/.zcompdump-vagrant-ubuntu-trusty-64-5.0.2:1256> _postpatcomps=( '(p[bgpn]m*|*top[bgpn]m)' _pbm '(texi(2*|ndex))' _texi '(tiff*|*2tiff|pal2rgb)' _tiff '-value-,(ftp|http(|s))_proxy,-default-' _urls '-value-,LC_*,-default-' _locales '-value-,*path,-default-'
_directories '-value-,*PATH,-default-' _dir_list '-value-,RUBY(LIB|OPT|PATH),-default-' _ruby '*/X11(|R<4->)/*'
_x_arguments 'yodl(|2*)' _yodl )
+nvm:409> PATH=+nvm:409> nvm_strip_path /usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games /bin
+nvm:409> PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games
+nvm:411> PATH=+nvm:411> nvm_prepend_path /usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games /home/vagrant/.nvm/versions/node/v5.0.0/bin
+nvm:411> PATH=/home/vagrant/.nvm/versions/node/v5.0.0/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games
+nvm:417> MANPATH=+nvm:417> nvm_strip_path /home/vagrant/.nvm/versions/node/v5.0.0/share/man:/usr/local/man:/usr/local/share/man:/usr/share/man:/opt/jdk1.8/man /share/man
+nvm:417> MANPATH=/usr/local/man:/usr/local/share/man:/usr/share/man:/opt/jdk1.8/man
+nvm:419> MANPATH=+nvm:419> nvm_prepend_path /usr/local/man:/usr/local/share/man:/usr/share/man:/opt/jdk1.8/man /home/vagrant/.nvm/versions/node/v5.0.0/share/man
+nvm:419> MANPATH=/home/vagrant/.nvm/versions/node/v5.0.0/share/man:/usr/local/man:/usr/local/share/man:/usr/share/man:/opt/jdk1.8/man
+nvm:420> export MANPATH
+nvm:422> export PATH
+nvm:424> export 'NVM_PATH=/home/vagrant/.nvm/versions/node/v5.0.0/lib/node'

Answer 1

I figured out what the problem was. Based on @L. Levrel's comment, I added an echo statement to the .zshrc, since he said that ssh login shells are both interactive and login. And sure enough, the .zshrc gets sourced AFTER the .zprofile, and the path is being overwritten in .zshrc. Moving the export command for the Java variable to ~/.zshrc solved the problem.