Volkswagen is turning off unionized workers' BlackBerries after work.

At Volkswagen, workers aren’t the only ones punching time-clocks. BlackBerries are punching out after each shift too.

The company has worked out a deal with unionized workers at its German sites to throttle their post-work BlackBerry use. VW is going to turn off messaging for these workers a half-hour after the workday ends, and flip the switch back on a half-hour before the next workday starts.

In all, 1,154 non-managerial VW BlackBerry users are affected by the agreement, according to the Wolfsburger Allgemeine Zeitung, which first reported the story.

The idea is to keep employees from feeling chained to their smartphones, and to send a message to bosses that it’s not reasonable to expect employees to be reachable at night, according to the Allgemeine Zeitung.

No word on whether any VW go-getters who might actually want to check their email during off-hours will be allowed this privilege.

Letting workers use their smartphones outside of work might be a good idea. It turns out that these are the hours when people use smartphones the most, according to Jeff Pierce, manager of IBM’s mobile computing research group, who has studied mobile device usage at IBM.

“Between when people wake up and when they arrive at work, this is when you use your smart phone,” he said earlier this month during a presentation at IBM’s Almaden research facility. “It’s on your bedside table, you roll over and grab it and you look at stuff before even getting out of bed.”

“Once you arrive at work, and between when you go home, this is primarily laptop time — or desktops for those who still have them.” There’s another smartphone usage spike around dinnertime, he said.

There is a bright side to VW’s plan, though. VW employees will still be able to use their BlackBerries during that critical 2-3 pm hour, when mobile phone use typically spikes during dull afternoon meetings.

VW’s connectivity kabosh apparently does not apply to workers outside of Germany. Reached on vacation, Vokswagen U.S. spokesman Guenther Scherelis said he didn’t have any information on the policy, but would forward Wired’s request to his German colleagues.

He was doing this via BlackBerry he added.

VW isn’t the only company looking to curb email use. European information technology vendor Atos said earlier this year that it wants to ban email completely by 2014.

Are you or your company waging a war on email? Tell us about it, er, via email: robert_mcmillan [at] wired.com.

(Photo courtesy: Ed Yourdon/Flickr)