the blossom end rot is a calcium deficiency and fairly simple to correct. the ones with it already aren't going to be good just pick them off and go on about it your day. spray the plant with a mixture of epson salt about 1 tablespoon per gallon. and if you mix in your normal fertilizer your good to go. some people say there is better out there but i have never had any problems w/ the above route.
and dark there is a sevin dust, same as the liquid but if it rains you need to reapply it
Shoulda done it already then, we haven't had real rain here in almost 2 weeks...