Q.How to look after grapefruit trees after fruiting
I have had my first crop of ruby grapefruit and they were beautiful and full of juice. Now I have picked the last of the fruit. What is best treatment I can do for my two trees? Some of the leaves are turning yellow. The trees are about 4 years old.
Yellowing leaves can indicate a watering issue, to much or to little.
Add water if you feel it's dry. Mulching with 2 to 3 inches of hardwood mulch.
Here are some links for you with more information.
https://www.gardeningknowhow.com/edible/fruits/grapefruit/grapefruit-tree-not-producing.htm
https://www.gardeningknowhow.com/edible/fruits/grapefruit/growing-grapefruit.htm