50 percent humidity The lemon tree grows in semi-tropical regions of USDA hardiness zones 9 to 11, but it can be an excellent indoor plant in cool regions as well. It’s a relatively easy-going ...

Once your seedlings begin to grow, remove the cover and place them in a brightly lit area. Once your lemon tree is big enough to produce leaves, it can be moved outside in USDA zones 9 through 11.

When a friend asked me why her lemon tree, despite diligent fertilization, had bright yellow leaves and was failing to thrive, I told her I would try to determine the ...