Does one recite a Beracha before eating a lemon?
Lemons, of course, grow on trees and, as such, should perhaps require the Beracha of "Bore Pore Ha'etz" which is recited over all fruits. On the other hand, since lemons have a bitter, acidic taste and therefore are not normally eaten directly, one might argue that eating a lemon does not require the recitation of a Beracha.
The Kaf Ha'haim (Rabbi Yaakov Sofer, 1870-1939) addresses this question in Siman 204 (Se'if 24; listen to audio for precise citation) and rules that the Halacha depends on the particular nature of the lemon. If the lemon is simply inedible, then one who forces himself to eat it does not recite a Beracha, since partaking of such a lemon is harmful. If, however, the lemon has only a mildly bitter taste, and thus could be eaten albeit with some difficulty, then one who partakes of the lemon must recite the Beracha of "She'hakol." The third category consists of lemons that actually have a sweet taste, over which one must recite the Beracha of "Bore Peri Ha'etz."
The lemons that are generally used today fall into the second category described by the Kaf Ha'haim; namely, they have a mildly bitter taste and can be eaten with some difficulty. Thus, as a general rule, one who eats a lemon nowadays should recite the Beracha of "She'hakol."
If a person adds sugar or another sweetening agent to a lemon, thus rendering it tasty, would he then recite "Bore Peri Ha'etz" before eating it? On the one hand, he partakes of a tasty fruit, an experience which normally requires the recitation of "Bore Peri Ha'etz." Conversely, however, one might argue that since the sweetness originates solely from the sugar, and not from the fruit itself, one should not recite the Beracha of "Bore Peri Ha'etz."
This issue is subject to a debate among the Halachic authorities. Rabbi Moshe Halevi (Israel, 1961-2001), in his work Birkat Hashem (vol. 3, p. 39), cites the Kaf Ha'haim (listen to audio for precise citation) as ruling that even in such a case one recites the Beracha of "She'hakol." Since the taste of the lemon itself is a sour one, and only the added sugar lends it a sweet flavor, it does not warrant the recitation of "Bore Peri Ha'etz." Nevertheless, Rabbi Moshe Halevi concedes that if one mistakenly recited the Beracha of "Bore Peri Ha'etz" over a sweetened lemon, he has nevertheless fulfilled his obligation and should not then recite "She'hakol." Hacham Ovadia Yosef, however, in his work Yabia Omer (vol. 8, Orah Haim section, 22:23), maintains that one should, in fact, recite "Bore Peri Ha'etz" over a sweetened lemon, since it is flavorful and does not taste sour.
Summary: if one partakes of a lemon that has a sour taste but can be eaten with some difficulty as is the case with most lemons sold today then he recites the Beracha of "She'hakol." If sugar or some other sweetener was added to lend a sweet flavor to the lemon, then according to some authorities one who partakes of the lemon recites "Bore Peri Ha'etz," whereas others maintain that even over such a lemon one should recite "She'hakol."
