Edible plant

This is a list of vegetables which are grown or harvested primarily for the consumption of their leafy parts, either raw or cooked. Many plants with leaves that are consumed in small quantities as a spice such as oregano, for medicinal purposes such as lime, or used in infusions such as tea, are not included in this list.

Humans have used leaves as food since time immemorial. Different types of leaves, depending from the place and the season, were part of the human diet since prehistoric times. Traces of edible leaves have been found in ancient Egyptian archaeological sites. Some edible leaves were historically documented in ancient Greece, in ancient Rome, in ancient Sri Lanka and in the Middle Ages. With the passing of the centuries many of those traditional leaf vegetables have been replaced by leaves that are more tender, have a more neutral taste or that are considered more refined. The leaves that were part of ancient traditional diets are still to be found in the wild, sometimes at the edge of cultivated fields, or near abandoned homesteads. Generally they are found not far from inhabited places, indicating that they are the vestiges of ancient cultivated plants.

There are places, like the Italian region of Liguria, where it is customary to go to the fields in spring to gather different kinds of edible leaves. These are later boiled to prepare preboggion, a local green mixture, that is generally used to stuff ravioli-like pasta. Also in Greece the tradition of eating a great variety of different leafy greens gathered in the fields has been preserved. These are eaten as a dish called horta.

Moderate quantities of edible leaf vegetables that are proportionate to amounts in local dishes, according to culture and place, are harmless unless there are allergies to chemicals in the leaves. For example, some people are allergic to celery leaves. At any rate, it is advisable not to eat large quantities of any particular leaf for protracted periods.

Some species, such as spinach and amaranth, contain oxalic acid. They should not be eaten on a regular basis without boiling and discarding the water. Also plants containing oxalic acid should be cooked in a steel pot or pan, not in aluminum pots.

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Wikipedia