Controlling ftp access with vsftpd

I'll preface this with the fact that I'm a bit of a newb with linux and especially with vsftpd. However, I had it set up such that I was able to upload files to a VPS I set up. The only problem is that I could not create directories. I set up vsftpd to disallow anonymous users, but allow virtual users to connect with their local credentials. At this point, the error message when I tried to create a folder changed from '550: Create directory failed' (I'm paraphrasing) to '550: Permission denied'. root owns the /var/www folder, and user with which I was authenticating had read and execute permissions but not write, so it makes sense that I wouldn't be able to create folders or files.

At this point I tried using chown and chmod to recursively change the group ownership to a group that my user was in and give my user write permission. This seemed to work at first - in the SSH session, I was able to cd to /var/www and create a new directory. However, when I tried to log in with my ftp client, I was now denied access.

What's even weirder is when I checked /var/log/vsftpd.log, I see the following lines:

Mon Jan  5 00:03:25 2015 [pid 801] CONNECT: Client "73.53.82.111"
Mon Jan  5 00:03:25 2015 [pid 800] [gradinafrica] OK LOGIN: Client "73.53.82.111"

...even though the login doesn't seem to work. What's going on?

PS I can provide vsftpd.conf on request