I have 3 varieties all from seed, some in growbags in the greenhouse, some in pots outside, some directly in the ground outside. They have all stopped growing at two trusses, and the flowers have not opened and are dying, as are some of the plants. The ones in the greenhouse are the worst. They have been watered regularly.
Tomatoes Dieing Off Early
Certified GKH Gardening Expert
In the greenhouse what are the temperatures. Though Tomatoes need warm weather, if the temperature is too hot, they plants will suffer.
Check that the soil is well draining. These links will help you pinpoint the issue.