Planted Pesto potatoes

I planted it last year, this time it has grown by itself from the roots and has grown without care. Organic and inorganic fertilizers were not found. Even then it has been good. It has been in the vine. There are potatoes under the ground, I will not pick them. Then next year there will be trees from here. Once I planted it under the ground and waited, the vine blossomed like a bunch of grapes, but it did not bear fruit. However, I found eight kg of potatoes under the ground.