I have two Brandywine and two Big Boy tomatoes. They are planted in large plastic pots (15 gal. approx). They have many blossoms, but the blossoms are dropping off at the stem about 1/2 inch above the blossom.
This is my first year in Zone 6 and the first year I've tried to grow tomatoes in many years. I have no idea what's going on. We had an invasion of little green (not hornworms) caterpillars in May and early June. I haven't seen any more of them and there seemed to be little clear bumps on the trunks and stems that I sprayed with a combination of dishsoap and mouthwash in water and then blasted the plants with water and they seem much healthier. But the blasted blooms are falling off.