Dill is a tasty herb with blue-green foliage, hollow stems, and yellow umbel flowers. It’s easy to grow in the majority of USDA zones and zings up casseroles, soups, and sandwiches with its seeds and foliage. Let’s find out more about this pickling staple, but first is dill a perennial or annual or something else?
Dill: Perennial or Annual?
Dill is technically a biennial but it’s grown as an annual and a perennial too! The confusion is a result of growing zones. In its natural habitat, dill germinates and grows foliage. Then it rests over winter before flowering and setting seed. Once it sets seeds it usually dies off. However, in very cold zones dill is grown annually because the freezing winter weather kills it. New dill growth is also the tastiest, so even in warm climates some gardeners choose to harvest it in the first year. If dill flowers (and therefore seeds) are removed in very warm zones it’ll behave like a perennial growing year-round and trying to set more seed.
USDA Growing Zones for Dill
Dill can cope with 25F (-3 Celsius) so it’ll grow in zones 2-11. Let’s break it down further:
- Perennial Dill zones 9-11
- Biennial Dill zones 2-8
- Annual Dill – Anywhere cooler than Zone 2
What Does Perennial Mean?
Perennial means a plant that lives longer than 3 years. Perennials are sometimes deciduous which means they lose all their foliage over winter to survive as a root ball, or they’re evergreen such as thyme.
When it’s grown in hot tropical zones, and its flowers are removed, dill is a perennial evergreen.
Annual plants do all their growing in less than one year from germination to setting seed and dying.
In zones that stay below freezing for long periods of time dill is an annual. Dill is also grown annually by gardeners who want the tastiest foliage because young leaves have the strongest taste.
Biennials are plants that germinate, then go dormant over winter before flowering and setting seed the following year. Bi means two and biennials live for two years.
Dill is naturally biennial in its native habitat and zones 2-8.
Is Dill A Herb or a Vegetable?
Dill (Anethum graveolens) is an herb in the Apiaceae family and the only species in the Anethum genus. It’s related to parsley, parsnips, carrots, cilantro, anise, and caraway but it’s tall and wispy fennel that it most resembles.
Native to Europe and Asia, dill can reach 3-5 feet tall if it’s grown as a perennial rather than an annual. Annual dill reaches around 24 inches. It has wide feathery leaves and white -yellow umbel flowers that resemble an umbrella.
History Of Dill
Where dill got its name is a mystery. The genus name Anethum is Greek for strong-smelling and in English it’s the old Norse word dylla for soothe.
The old Norse name refers to its use as a stomach settler and medicinal herb, but it was also used in antiquity across the world. 3000 years ago, the ancient Egyptians used dill as an aphrodisiac and for defense against witches, and in the 1st century AD the Roman considered it a symbol of good luck.
Today in the West it’s mostly used as a pickling spice and modern medicine is investigating it’s potential to fight diabetes. You can read more about it in the Journal of Tropical Medicine.
Does Dill Survive Winter?
Yes, dill can survive a winter down to 25 degrees Fahrenheit (minus 3 Celsius) if its roots are well drained. It’s a cool weather European herb, not a Mediterranean sun worshipper, although it appreciates a sunny spot to grow in.
How To Grow Dill
If you’re growing dill as a biennial or annual not a perennial then it’s best seeded in early spring after the frosts have passed. It’s a fast germinator that can appear just ten days after it’s sown! When the seedlings appear it’s best to thin them out to 6 inches apart.
Dill likes well-drained soil that’s rich in nutrients plus plenty of light. The temperature doesn’t need to be high, but lots of sunshine will increase the harvest. Like carrots, dill puts down a long tap root, so it doesn’t like being transplanted. If you’re growing dill in a container, make sure it’s at least 12 inches deep.
Keep seedlings weeded and well-watered because dill doesn’t like to dry out. If it dries out it will ‘bolt’. That means it’ll produce seeds much earlier. Harvest foliage in spring and summer, flowers as they appear, and seeds in late summer.
Should I Cut Dill Back?
You can cut up to 1/3 of a dill plant at one time, but it’s best to pick foliage regularly to avoid shock. If you’re growing biennial or perennial dill cutting it back by 1/3 in fall will help train it into a bushy plant and avoid damage from strong winter winds.
Is Dill Still Good After Flowering?
Yes, because its seeds will develop and they have the strongest flavor. You can continue to harvest the foliage after its flowered too.
What Butterfly Likes Dill?
Dill flowers are popular with beneficial pollinating insects, so they will attract plenty of wildlife to your garden.
Black and Anise swallowtail butterflies use dill as a host for their green, black and yellow striped caterpillars. Females lay eggs on its foliage and the young caterpillars munch their way across the dill plant before cocooning and emerging as a beautiful swallowtail.
Is Dill Safe For Dogs?
According to the ASPCA’s poison control database dill is not toxic to dogs, cats, or horses but prolonged contact can cause dermatitis.
In fact, dill is packed with vitamins and healthy antioxidants, but it’s never a good idea to let pets chew on garden plants. If you want to give dill to your pets, use a safe quality supplement recommended by a veterinarian.
It’s never satisfying when there isn’t a straight answer! However, we can say that dill is natively a biennial but it can be grown as an annual if you prefer, and in tropical climates it can live for years as a perennial.
If you want the tastiest dill for the kitchen then grow it annually, but wherever you are, give dill a go. It’s a tough and versatile herb that adds an interesting flavor to soups, sandwiches, fish, eggs, and of course pickles!
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- Royal Horticultural Society, Available here: https://www.rhs.org.uk/herbs/dill/grow-your-own
- ASPCA, Available here: https://www.aspca.org/pet-care/animal-poison-control/toxic-and-non-toxic-plants/dill