Dill (Anethum graveolens) is an annual herb in the celery family Apiaceae. It is native to North Africa, Iran, and the Arabian Peninsula; it is grown widely in Eurasia, where its leaves and seeds are used as a herb or spice for flavouring food.
When used as a companion plant, dill attracts many beneficial insects as the umbrella flower heads go to seed. It makes a good companion plant for cucumbers and broccoli.
Tomatoes will benefit from dill when they are young since it will repel harmful pests while attracting pollinators, but as dill matures and flowers it will slow or stop the growth of tomatoes. Prune dill regularly so it does not flower if planted next to tomatoes.
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Dill- Anethum Graveolens
Dill grows up to 1.5–5 feet (0.46–1.52 m) from a taproot like a carrot.
Its stems are slender and hollow with finely divided, softly delicate leaves; the leaves are alternately arranged, 10–20 cm (4–8 in) long with ultimate leaf divisions are 1–2 mm (1⁄32–3⁄32 in) broad, slightly broader than the similar leaves of fennel, which are threadlike, less than 1 mm (1⁄16 in) broad, but harder in texture.