The Lemon OG strain is actually a cross between the Las Vegas Lemon Skunk and The OG #18.
The effects of this strain make you feel sleepy and relaxed so that you can get rid of stress, and rid yourself of anything that is irritating you. The strain is good for people who want to sleep and are having trouble doing so.
Mostly though, Lemon OG is bred for an unmistakable lemon taste and smell. It is the lemoniest of the crosses being bred, and since users like the lemon, expect the strain to become more lemon and less kush/skunk/diesel, increasing its terpene profile of limonene while phasing out the taste of Kush.