If you must substitute, see below:
Dill seed is not a good substitute for fresh dill weed because of the difference in flavor strength but it does depend on the recipe. The seed has a camphorous, slightly bitter flavor, and the weed has a delicate flavor. The differences are like night and day.
Do you know how much dill seed is equivalent to one head of fresh dill?? I am going to make pickles, and fresh dill is not available. Thanks in advance for your help. – Judith Cartwright (8/22/01)
3 heads dill = 1 tablespoon dill seed
1/2 ounce dill seed = 1/2 cup fresh dill
3- to 5-inch sprig of fresh dill = 1/4 teaspoon of dried dill weed.
Fennel seeds are another substitute for dill seeds. Fennel seeds have a flavor similar to that of anise. When added to a dish, fennel seeds add a sweet aroma to it.
If you think of a delicate herb that is still capable of freshening up a dish, dill will be one of the first options to come to your mind. While the flavor of both dill weed and seed is unique, there are other great options in case you need to substitute them.
As opposed to the mild flavor of dill weed, dill seeds are more pungent. Compared to the sweet and grassy notes of dill weed, dill seeds have a slight bitterness. Dill seeds are also described as somewhat nutty.
3. Celery Seeds
Fennel fronds have an appearance similar to dill. Chopped and tossed on a dish you may not even see the difference between the two. Fennel leaves are the perfect garnish for dishes that need a little bit of lightness and freshness.
Coriander seeds are a milder alternative for dill seeds.
You can use coriander seeds both whole and ground. Ground seeds are better when you are trying to evenly distribute the seeds in doughs.
Dill can be substituted with various soft-leafed herbs, basil being one of them.