DarkGrowSeed Bank
Seed saving · Ocimum, Coriandrum, Anethum, Petroselinum, Mentha

Saving herb seed

The most varied group for seed saving: basil and coriander are annual, parsley is biennial, and mint rarely sets true seed at all and is divided instead.

Saving herb seedAnnual / biennial / perennial — varies
Life cycle
Annual / biennial / perennial — varies
Pollination
Insect-pollinated
Isolation
150 m–800 m
Seed life
2–5 years
Yield
1 plant gives 100s–1000s seed

Herbs are not one group when it comes to seed. Basil and coriander are annual and set seed in the same season. Dill is annual and shatters violently. Parsley is biennial and needs a winter. Mint is perennial and is propagated by division because seed-grown mint is rarely true to type.

All are insect-pollinated and cross readily within their genus — and dill crosses with fennel, which is a different genus in the same family.

The protocol

  1. 1

    Know which type you have

    Annual (basil, coriander, dill): seed this year. Biennial (parsley): overwinter, seed next year. Perennial (mint): divide, do not bother with seed.

  2. 2

    Let a plant flower

    Stop harvesting from it entirely. Basil produces a spike of white flowers; coriander and dill produce umbels of tiny flowers.

  3. 3

    Watch for shattering

    Dill and coriander shatter the moment seed is ripe. Check daily once the heads turn brown, or bag them.

  4. 4

    Cut heads into a paper bag

    Cut the whole head and put it in a bag upside down. As it dries, the seed falls out on its own.

  5. 5

    Dry, clean, store

    A week in the bag, then winnow. Basil seed keeps four to five years; dill and coriander three to four. Parsley is short-lived at two to three.

What goes wrong

Dill and fennel. They cross, and the offspring is a plant that tastes of neither. Never grow both for seed in the same year.

Basil varieties crossing. All Ocimum basilicum varieties cross — Genovese with Dark Opal gives a muddle. 150 m is the honest figure.

Mint from seed. It will not come true. Divide the plant instead.

Parsley's winter. It is biennial, so a parsley plant that flowers has finished its leaf production. Save seed from a plant you are prepared to lose.

Growing it first? The full cultivation guide — sowing, feeding, harvest — is at Growing herbs indoors.
DarkGrow forum

Saved seed from this crop?

Germination rates, what came true and what crossed — post it and let other growers learn from it.

Open the forum → Start a discussion

All 14 protocols

Annual, biennial and vegetative crops all save differently. The index compares them side by side.

Seed saving index Isolation distances