You can do that by following the "Deleting my entire Google+ profile" procedure. I've done it few weeks ago and unless Google has changed which services get deleted along, you have nothing to worry about.
Your Google+ profile will be deleted along with other services and data that depend on your Google+ profile.
What to do:
Sign in to Google+.
Click on your full name or email address in the top-right corner of your screen.
In the Account Management section, click Delete profile and remove related Google+ features.
Select Delete your entire Google profile.
One question: with everything seemingly requiring a google+ account these days - what other services here do you end up getting rid of?
I think Google is trying to inflate its G+ numbers in order to seem competitive with Facebook, so its basically a dick-size contest with users getting caught in the middle.
Your Google+ profile will be deleted along with other services and data that depend on your Google+ profile.
I wonder what would happen to my old Blogspot blog that has hundreds of entries. And photos in that blog, that were uploaded to Picasa through Blogspot before G+ even existed.
I can see that Blogspot album in G+, so it might be data associated with G+ and it would be deleted. We spent hundreds of hours writing and taking those pictures, so it would be a shame to have all that hard work deleted because of a vague what gets deleted description.
Deleting my entire Google+ profile
Your Google+ profile will be deleted along with other services and data that depend on your Google+ profile.
What to do:
Sign in to Google+. Click on your full name or email address in the top-right corner of your screen. In the Account Management section, click Delete profile and remove related Google+ features. Select Delete your entire Google profile.
One question: with everything seemingly requiring a google+ account these days - what other services here do you end up getting rid of?