Fennel and dill are similar plants with soft, pinnate leaves and clusters of small yellow flowers in the umbels. Both plants are fragrant and carminative and facilitate digestion. However, you can quickly tell them apart if you smell or taste them.
This guide covers the key differences between dill and fennel plants and clarifies why they are used for different purposes.
The main characteristics of dill and fennel: botanical classification
Dill and Fennel are two different herbs from the same plant family, Apiaceae. However, they belong to other genera and species that distinguish them.
In Latin Anethum graveolens, dill is an annual herb native to North Africa, Iran and the Arabian Peninsula. It is widely cultivated in Eurasia, where the leaves and seeds are used as herbs or spices to flavor food (1)
On the other hand, fennel (Foeniculum vulgare) is a robust, herbaceous, perennial herb native to southern Europe and the Mediterranean and was probably cultivated by the ancient Greeks and Romans. (1)
Although dill is only one, the genus Foeniculum vulgare includes three different groups:
- Florence fennel, grown for the bulb used in cooking;
- Sweet Fennel, grown for fresh leaves and sweet fruits – fennel seed
- Bitter Fennel, grown for its bitter-tasting fruits, is mainly used in cosmetics.
Dill and Fennel are both aromatic plants that are considered invasive or weedy and are exceptionally easy to grow. They also attract butterflies.
Dill and Fennel: Difference in appearance
to leaf through
Although dill leaves look very similar to those of Fennel, fern-like dill leaves are slightly broader and finely divided into thread-like segments, creating a lacy and airy texture.
Fennel fronds, also called feathery fronds, have a similar dissected structure, but a slightly different arrangement.
Fennel also produces thin leaves that are bright green, but when crushed they give off a distinct anise-like scent.
stems
Their hollow stems, known as umbellifers, look much the same, but fennel can grow up to 2 m tall, while dill can grow 40 – 150 cm tall.
flowers
Both members of the Apiaceae family produce small yellow flowers that bloom in clusters called umbels.
fruits
Dill seeds come from dried fruits that are 4-5 mm long, 1 mm thick, and have a straight to slightly curved shape with a ribbed surface. Dried dill seeds are often used in pickling.
Fennel seeds, on the other hand, are twice as long as dill seeds and slightly curved. The fruit from which fennel seeds emerge is a dry schizocarp 4–10 mm long.
lamp
Although fennel fronds can be used in salads, the fennel bulb is the most commonly used part of the plant, while dill plants do not have a bulb. Fennel bulb is a versatile, mild vegetable that is delicious fried or grilled in Mediterranean dishes or raw in salads.
If you’re trying to identify Fennel, the white bulb at the base of the stem clearly distinguishes Fennel from other members of the Apiaceae family, such as anise or the carrot plant.
Fennel versus dill: taste and smell distinction
Dill and fennel are similar in appearance and have a different flavor profile. Fennel has a very distinct taste of black licorice, which is lacking in dill. Dill has the same faint sweetness as fennel, but has more of a herbal, grassy flavor.
Depending on their scent, you can quickly distinguish these plants from each other, as dill has a sharper aroma than fennel, especially if you gently rub the leaves between your fingers.
Dill and fennel may look similar and share a licorice flavor, but I don’t recommend using fennel as a substitute for dill because it doesn’t taste like dill at all.
Dill vs. Fennel: Can These Herbs Grow Together?
Both dill and fennel can be grown from seeds, but it is recommended to plant dill seeds in the spring and fennel seeds in the fall.
Dill thrives in cooler weather, making spring and fall the best seasons for planting. In warm weather it tends to seed and die out, but can reappear if the seeds are left alone. On the other hand, fennel can grow all year round and even survive mild winters. Regular pruning also helps control its size.
Plant both herbs in sunny to partially sunny locations, but make sure they don’t grow too close together as they can cause cross-pollination, which can affect the flavor. If you plant them in the same garden, separate them with rows of other crops or use separate pots. Make sure the soil is rich in organic matter and well-drained. Wait to fertilize until the plants are well established. Cover the developing bulb with mulch or soil for fennel grown for bulbs to maintain tenderness.
Culinary applications
These two are widely used in kitchens around the world for various culinary purposes. Fennel is versatile; the whole plant is used in cooking, both raw and roasted, while dill is primarily an herb and garnish.
Fresh dill
Dill is often used fresh in salads, dips and sauces. Northern European cuisine uses dried dill leaves in soups, pasta, stews and cooked dishes such as gravlax. Dill is an important ingredient in making dill pickles.
Dill is a versatile herb that is best used fresh in salads, although freeze-dried leaves retain their flavor for several months.
With a caraway-like taste, the dill seed is used as a spice and dill oil is extracted from various parts of the plant.
Fennel
Wild fennel flowers, known as ‘fennel pollen’, are vigorous but expensive.
Dried fennel fruit is an aromatic herb with an anise-like flavor, best when green for cooking. Roasted fennel fruits are consumed as mukhwas or candied. Fennel seeds are found in paan, a popular breath freshener in parts of India.
The white bun is crispy and can be fried, stewed, braised, grilled or eaten raw. The Fennel shines in the Mediterranean kitchen.
Florence fennel is one of the three main herbs used to prepare absinthe.
Young leaves add flavor to salads and garnishes, while leaf bases and shoots can be eaten like celery.
