Could you help me correct this one please?

Nearly five years ago before, and with the help by of our father, my sister and I planted some cherry tomatoes in our back garden (in the backyard). Since then——for all these year——we had been allowing tomatoes to self-seed where they please. As a result, the plants are growing everywhere somewhere. The fruits are is small in size, but juicy and tasty. There's are so much of it that we often share it with our neighbours (UK English). Although we allow tomato plants to grow in the same place year after year, but they have never caught any disease, nor have they been attacked we have never had any disease or  by insects. We are growing wonderfully tomatoes at no cost!