Used to flavor many dishes such as salads, sauces, meats, and seafood, fresh dill is a delicate, aromatic herb. Though it's available dried, dill's distinctive flavor does not translate to its dehydrated form—we really don't recommend substituting one for the other. When cooking with fresh dill, be sure to add it at the end of the cooking time because tender herbs lose their fragrance and flavor quickly when heated.
The more tender the herb, the closer to cooking time you'll need to chop it. If you chop dill in advance, cover it with plastic wrap punctured with a few air holes and refrigerate. You can save leftover chopped herbs for a day or so, but sniff them before using, because dill is highly perishable when chopped.
Tender herbs like dill need special attention so they don't blacken or freeze in the refrigerator. To keep dill at it's best, remove any rubber bands or fasteners. Because the roots draw the moisture from the leaves, it's important to trim off the root ends and the lower parts of the stems to prevent the tops from wilting.