was your growing conditions the same the last 2 years.
watering
temps
soil ph
same plants etc....

Pretty much except the pruning...

There is no documented correlation between not pruning and the incidence of BER. Indeed there is more evidence that the stress created by pruning can contribute to it.

This is not to say there is no effect, just that it may be nothing more than coincidence. Especially when one considers that commercial growers don't generally prune their plants either.

However the correlation between weather, the primary variable and beyond your control, and the incidence of BER is well documented.

Anecdotal info is that I too use Earthboxes and have for many years and I never prune. Yet some years I have early BER and some years I have none. So far this year has been quite BER-free but then we haven't had nearly the rainfall we had last year either when my BER was moderate to severe early in the season. And yes, it always goes away no matter what we do.

Some have a tendency to focus desperately on BER rather than just accepting it as a common factor in growing tomatoes. Just like hornworms and early blight. The hope is to ID the cause and thereby find the CURE when the 2 primary causes - plant immaturity and inconsistent spring weather - are beyond our control in the first place. :)

Dave

Conditions here in the north east have been TOTALLY different from last year. We've had a very mild, virtually snow free, extremely dry winter and spring. I'll bet Memorial Day will be as warm as the Fourth of July. I don't expect my plants to respond this year like they did last year.