The leek, along with onions and garlic, belongs to the genus Allium, and the leek cultivars may be treated as a single group called Allium porrum. The cultivars can be subdivided in several ways, but the two most common types are:
1. “Summer” Leeks – intended for harvest in the season when planted. They are the smaller of the two common types.
2. “Over-wintering” Leeks – meant to be harvested in the spring of the year following planting. They are generally the more strongly flavored of the two common types.
Instead of forming a tight bulb like onions, the leek produces a long cylinder of bundled leaf sheaths – not stalks or stems – that are generally blanched by pushing soil around them (trenching). Leeks are easy to grow from seed, and once established in the garden they are very hardy and rarely have pest or disease problems. They can be bunched and harvested early when they are about the size of a pencil, or they can be thinned and allowed to grow to a much larger mature size.
Leeks have a mild onion-like taste, and if eaten raw, they are enjoyably crunchy and firm. The edible portions of the leek are the white base of the leaves (above the roots and sheath base) and the light green parts. To a lesser extent, the dark green parts of the leaves are sometimes used. Leeks are typically cut into thin slices, and they have a tendency to fall apart due to the layered structure of the leek. The different ways of preparing the vegetable are:
1. Boiled, which turns it soft and creates a milder taste. One of the most popular uses is for adding flavor to soup stock.
2. Fried, which leaves it crunchier and preserves the original taste.
3. Raw, which makes it a perfect salad ingredient.