Lemon peel and Lemongrass essential oils have different properties and can be used for different symptoms.

Lemon Grass, Cymbopogon citratus, contains 87% ciitral. Properties include calming and tonifying. The high amount of citral irritates damaged or sensitive skin and must always be diluted with only 2-3 drops in a one- ounce carrier oil blend. Citral is a potential allergen and can also raise ocular pressure in glaucoma causing damage. Use sparingly with caution.

Psychologically, lemon grass increases awareness of yourself, others and the environment.

Lemon peel, Citrus Limonium, is 72% d-limonene, a monoterpene hydrocarbon and has a potential as a stimulant with drying properties. It also contains coumarins, common in many essential oils. 

Lemon peel is photo toxic and should not be applied before sun exposure. It also should be diluted in a carrier oil. Only 2 drops are needed for a one- ounce blend. In blends, it is used as a top note.

To recap, lemon grass is calming, and lemon peel is a "pick me up". Keep both refrigerated to maintain freshness in small bottles to reduce oxygen as you use the essential oils in various blends.