As an avid gardener and seed saver, I love harvesting my own leek seeds each year. Leeks are biennials, meaning they take two years to complete their lifecycle and produce seeds. With a little planning and patience, you can easily save leek seeds from your healthiest plants for future harvests.
Overview of Saving Leek Seeds
Here’s a quick summary of the leek seed harvesting process
Grow leeks as normal in year 1. Select 3-5 of the best plants and allow them to overwinter.
In year 2, the overwintered leeks will send up tall seed stalks topped with seed heads.
Allow the seed heads to mature and dry completely on the stalks, Then collect and further dry indoors
Rub the dried seed heads to separate seeds from debris. Winnow or sieve to remove chaff.
Label and store seeds in a cool, dry place to plant the following year. Leek seeds remain viable for 1-2 years.
Now let’s look at each step in more detail.
Growing Leeks for Seed Saving
The first step is growing healthy leeks for seed production. Here are some tips:
Start leeks indoors 6-8 weeks before your last spring frost date. Harden off and transplant outside 2-3 weeks before the last frost.
Space leek seedlings 4-6 inches apart in rows 12-18 inches apart. This gives them room to size up.
Weed and water throughout the season. Side dress with compost or fertilizer to fuel growth.
As leeks mature in late summer, select 3-5 of the best looking, healthiest plants to overwinter for seed.
Mulch overwintering leeks well to insulate roots from cold. Remove mulch in spring as new growth emerges.
Letting Leeks Flower and Produce Seeds
In year 2, your overwintered leeks will transition from producing leaves to sending up tall seed stalks:
Flower stalks emerge and rapidly elongate in late spring. The seed head forms a globe shape on top.
Flowering typically takes place mid-summer. The leek flowers are pollinated by insects, especially bees.
Seeds develop through summer, gradually drying and darkening. By late summer, seeds are mostly mature.
Let seeds fully mature and dry on the stalks. Seeds are ready for harvest when flower heads are dry and papery.
Harvesting and Processing Leek Seeds
There are two approaches to harvesting dried leek seeds:
On the Stalk: Allow seed heads to dry completely on the plants. Tie paper bags around the heads to catch seeds as they drop. Collect the bags once fully dry.
Cut Stalks: When seeds look mature, cut stalks and hang upside down indoors in paper bags. Let them finish drying before rubbing off seeds.
To extract the seeds:
Rub the dried seed heads between your hands over a bowl to separate seeds.
Winnow or sieve the seeds to remove chaff. Alternatively, blow gently to float away chaff.
Pick out any debris, then transfer leek seeds to labeled envelopes or jars for storage.
Storing and Planting Leek Seeds
Once properly dried and packaged, leek seeds will remain viable for 1-2 years if stored in a cool, dry location.
Label envelopes with variety and year harvested. Store seeds in a refrigerator or other cool spot.
Plan to use seeds within 2 years before viability declines. Discard any unused after 2 years.
In future years, start leek seeds indoors 4-6 weeks before transplanting into the garden.
Saving leek seeds takes patience but it’s rewarding to plant next year’s crop from your own seed stock. I love growing unique leek varieties passed down this way for generations. With a little diligence, you can maintain your own seed bank of leeks adapted to your growing conditions. Enjoy the fruits of your seed saving labor!
Frequently Asked Questions About Leek Seeds
Here are answers to some common leek seed harvesting questions:
How long do leek seeds last?
Leek seeds typically remain viable for 1-2 years when properly stored. Label envelopes with the year harvested and sow within 2 years.
What do leek seeds look like?
Leek seeds are small and black with a pyramid shape similar to onion seeds. They are released from dried triangular seed pods.
How do you know when leek seeds are ripe?
Leek seeds are ready to harvest when the seed heads are dry, brown, and papery. Seeds will be dark in color. Flower petals will fall off when gently shaken.
Can you save seeds from grocery store leeks?
Generally most grocery leeks are hybrid varieties bred for leaf production rather than seed viability. You’re better off buying non-hybrid heirloom leek varieties from reputable seed companies if you want to save seeds.
Do leek seeds need stratification to germinate?
No, leek seeds do not require cold stratification. You can start leek seeds indoors in seed starting mix anytime from 4-6 weeks before transplanting.
How do you extract leek seeds from the seed heads?
Rub the dry brown flower heads between your hands over a large bowl. This will cause the seeds to fall out. Winnow or sieve to separate seeds from debris.
What is the best way to store harvested leek seeds?
Cool, dark, and dry. Put seeds in labeled envelopes or jars in the refrigerator or another location away from light, heat, and moisture. Adding silica gel packs helps absorb excess moisture.
Tips for Success with Leek Seeds
Here are a few final tips to help ensure success with saving leek seeds:
Select the biggest, healthiest leeks from your garden to overwinter for seed production.
If weather is wet, dry seed heads under cover to prevent mold before seeds mature.
Check seeds heads frequently as they ripen – seeds drop quickly once pods split open.
Rub and winnow carefully to avoid crushing tender leek seeds when cleaning.
Store cleaned seeds with silica gel packs to keep moisture levels low.
Test seed viability next season by sprouting a sample indoors before planting all.
Leeks have been used as a culinary crop for at least 4,000 years. Enjoy this historic allium in your garden and try your hand at biennial seed saving.
Sow leek seeds indoors 8-10 weeks before the last frost date. Seedlings can be transplanted outside as soon as the risk of hard frost has passed.
Plant leek seeds ¼ inch deep into flats. When transplanting leeks into your garden, space them 6 inches apart.
Leeks like soil rich in organic matter. They’re also a heavy feeder—meaning they prefer a high-nitrogen fertilizer.
Leeks can suffer from downy mildew, white rot, and leaf blight. Take care to rotate plant families in your garden to prevent diseases.
