Answer: Your tree is self fruitful so you do not need another tree. In order to fruit, the tree must bloom. When it blooms, to assure pollination, gently swab each flower with a soft paintbrush. Many of the blooms will probably drop without setting fruit. After fruit does set, do not be surprised if the tree self prunes most of the limes. The tree will only try to carry a limited number of fruit to maturity. How many it can bear successfully depends on its overall health. Since the tree is looking good and you did harvest one lime, it sounds like you are probably doing most things right. Here is some general information on container citrus you may find helpful as well. You may need to cut and paste the complete url into your browser to make it work correctly.
Good luck with your little lime tree!
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