Problems with my grapefruit tree

Question

I have a pot grown grapefruit tree approx a metre tall bought four years ago — has one pea sized fruit from last year and masses of bud that never sseem to open completely

Answer 1

These articles should help you with care.

https://www.gardeningknowhow.com/edible/fruits/grapefruit/growing-grapefruit.htm
https://www.gardeningknowhow.com/edible/fruits/grapefruit/hand-pollinating-grapefruits.htm
https://www.gardeningknowhow.com/edible/fruits/grapefruit/grapefruit-tree-not-producing.htm