Refrigerate fresh basil, wrapped in barely damp paper towels and then in a plastic bag, for up to four days. For slightly longer storage, you can place a bunch of basil in the refrigerator for up to a week. Set it in a glass of water, stems down, and put a plastic bag over the leaves, changing the water every two days. To preserve fresh basil, wash and thoroughly dry the leaves. Then alternate layers of leaves and layers of coarse salt, using a container that can be tightly sealed. Preserved basil keeps indefinitely on the shelf. Dried basil can be stored in a cool, dark place for up to six months. Fresh basil has a more defined flavour and a more fragrant aroma than dried basil. Note: Basil does not freeze very well.