Answer: If you started your lemon tree from a seed, it will take at least 7 years for it to mature enough to produce fruit. This may be your lucky year!
If your lemon tree was purchased at a nursery and is a grafted tree, it should flower and produce fruit at a much younger age. You didn't give us a clue as to where you live so we don't know if it is indoors or out. An outdoor tree needs full sunshine all day long; and indoor tree needs bright light during the winter months and should be taken outdoors during the spring and summer months. After acclimating it to the change in environments, slowly move your tree into a sunny position. It needs about 6 hours of direct sunshine during the spring and summer months.
Hope this information helps!
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