tree is only leafed out at bottom not on top although limes are alive. how do I bring it back?

Question

Tree only leafed out at bottom, not on top although lims are green in middle, how do I bring it back?

Answer 1

If you mean that it leafed out at the base of the tree, unfortunately that means that the tree is likely unsalvageable.

All commercially sold citrus trees are grafted. This means that there is one type of tree that makes of the canopy of the tree, called the scion, and another one that makes up part of the trunk and all of the roots, called the rootstock. Occasionally the scion will die off and the rootstock will reassert itself by growing from the bottom of the tree. But rootstock never produces quality fruit.

If you think you have a situation where the scion has died and the rootstock is regrowing, it is best to replace the tree.

Here is more information that may help:
https://www.gardeningknowhow.com/ornamental/trees/tgen/can-grafted-trees-revert-to-their-root-stock.htm