I had to click on that Cornell link, John. I find Cornell to be a wealth of information even tho' I live on the other side of the country from NY.
"Management Strategies: Since blossom end rot is so closely related to adequacy of the water supply, an important control is to regulate the moisture supply in the soil."
That's my problem every year but there's only a few of the fruit that end up with BER and then I usually get with the program and keep the soil moist enuf for the remainder of the season. My soil has calcium and that often is not the problem in many gardens but when the fruit starts to really grow quickly - adequate soil moisture becomes critical.
"If the irrigation of any kind is available, it should be used during periods of hot, drying winds." Ha! Obviously on the other side of the country from me. Hot, drying winds? Right at this moment in my tomato patch it is 96.1F, 20% humidity, with 4.0 mph from the ESE according to my friendly neighborhood weather station. Well, that's not much wind because it isn't from the W or SW.
Seems like it's just about always windy in my big veggie garden and the soil is glacial till. That's essentially gravel.
Anny, get your hands down in your soil and feel for moisture. There's lots of solar energy for growth right now. Be sure that there's adequate moisture for your plants.
Steve