Certain organic citrus tree leaves may be used as a wrap in cooking. But first make sure the leaves you get from a backyard lemon tree has never been sprayed with pesticides because the pesticides will poison you. You need organic, never-sprayed lemon tree leaves.
Wrap any meat or fish item in the leaves and grill your food. The lemon tree leaves will impart a lemony, citrus fragrance to the meat or fish. Here is an illustrated recipe for lemon-tree-leaf-wrapped Sicilian meat balls from the FXcuisine.com site. In areas where there are no lemon tree leaves, frequently bay leaves are wrapped around grilled meat or fish.
Recipes for meat or fish wrapped in lemon tree leaves and grilled are also found in numerous East Asian countries. Lemon tree leaves also are used in Thai and Vietnamese dishes.
Cooking with organic lemon flower petals
At the Greek-Recipe.com site, you’ll see recipes for using the organic flowers (no pesticides) from lemon trees in your cooking recipes. Basically, you wash off the stamens from the petals of a lemon tree. Then you put the cleaned petals in boiling water for 2-3 minutes. The petals are stored in a jar full of lemon juice diluted with a little water. You let the mixture stand for a couple of hours.
Then you boil a spoon full of sugar and water for a few minutes, usually about ten minutes, until the water turns to light syrup. You rinse the lemon juice off the petals you just took out of the jar and put the petals in the syrup. Then you boil everything for another five minutes. As the mixture starts to cool, you squeeze the juice of a lemon over it. Let it cool some more. And put the syrup in a jar. Store it in your refrigerator. 
To grow your own lemon tree indoors in containers close to natural sunlight, see the Citrus Growers cites. Also see the book, Lemon Tree Healthy Cooking (Paperback) by Sunny Baker Ph.D. Also try the recipes in the book for Tofu With Lemongrass and Coconut Curry Sauce or Lemon Shrimp on a Stick.
Lime leaves used in Thai and Vietnamese cooking are Keffir lime leaves which are a different plant than the usual lime tree leaves you see in California. Keffir lime leaves have odd-shaped twin leaves. Lemon tree leaves are used as wraps for meats, fish, veggie burgers/balls, or other vegetables. Don’t eat the tree leaves from lemons or keffir limes as you’d eat the fruit. The taste of lemon leaves is similar to lemongrass.
Lemon or keffir lime leaves are meant to wrap food with when cooking to give a flavor and scent, but not to eat. Grape leaves are edible when cooked. Wrap rice and tomato juice/paste, vegetables, and meat or fish with boiled and edible grape vine leaves. Also see the iVillage Garden Web for more ideas on which tree leaves are edible. Be sure to find out first whether the leaves are organic. Don’t use leaves that have been sprayed with pesticides in your food.
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