If you live in zone 5 or above, you can grow and harvest your own leek seed. Even if you live in a lower zone, with winter coverage, you can still harvest your own leek seeds. Save money and save healthy seed by learning to DIY this. We show you in simpHere’s how to grow and save leek seeds – this is a great seed save for beginner seed savers!
If you don’t need to know how to grow leeks, please feel free to skip down to the Save Leek Seeds section.
—>>>If you need to brush up on general seed saving information, please visit this link <<<—
Grow Leeks to Save Leek Seeds
Before you can save leek seed, you need to grow leeks – or know someone who is growing them. You may have heard that leeks are difficult to grow but I say, if you can grow a potato, you can grow a leek.
I always start my leeks indoors to give them a head start when I transplant them to the garden. I try to start most of my seeds indoors to avoid fluctuations in temperature and bad bug populations that might hard my baby plants.
When Should I Start Leek Seed?
I start leeks seeds inside about 10-12 weeks before the last spring frost so they are ready to plant outside about 8 weeks before my last spring frost.
I start another two rounds of leek seeds about about the 9 and 8 week mark before the last spring frost, as well. These can all be transplanted outside in staggered groups so that my family can harvest leeks for several weeks in the early spring.
I do the same thing for the fall garden. I start leek seeds indoors about 15-20 weeks before my first fall frost. Mature leeks, unlike baby leeks, can take some frost in the garden and do well.
Frost actually sharpens their flavor! I always start my fall leek inside and keep them inside as long as I can into late June and July to avoid my really hot and humid summer days.
I make sure that my summer planted baby leeks have some afternoon shade from other plants. If your summers are more mild than my midwestern US summers, feel free to plant your seedlings out as soon as they’re ready. They will take four to five months to mature.
How to Germinate Leek Seeds
Like most onions, leeks can take up to three weeks to germinate. Otherwise, use a standard seed starting mix to plant your leek seeds. If you have enough, plant leek seeds in individual pots to make transplanting seedlings SO much easier.
—>>>Click here to learn to Make Newspaper Pots for Seeds from Learning and Yearning.<<<—
Otherwise, plant leek seeds a few inches apart so their roots don’t tangle. Keep the dirt evenly moist as they germinate by covering them with a lid or plastic wrap. Leeks do not need light to germinate but they do need temperatures above 45F/7C.
Once your seedlings are several inches tall, and 6-8 weeks before the last spring frost, prepare to plant your leeks outside.
—>>>Follow this link to learn more about how to plant and grow leeks from A Garden for the House.<<<—
Let your crop grow up all season and save 3-5 of your best stalks to over-winter. Leeks are biennial plants, which means their natural life cycle is two years long.
They will produce a seed stalk in their second year. Cover your stalks for seed saving over the winter if you live in a cold climate.
Save Leek Seeds
To get a quick overview of how to save leek seeds, please watch this short video. Afterwards, come back to the article for more specific directions. I’m such a visual learner that I need to see steps first. If you’re like me, this video is for you!
As your leek harvest matures, select three to five of the best looking leek stalks and let them all go to seed in their second year of growth.That means, you want to look for the healthiest and fattest leeks you have and let them grow a flower stalk. The other stalks should be cut off to prevent spoiling the leek for its culinary use. If you’ve ever seen any member of the allium family flowering, you’ll recognize a leek bloom immediately.
The flower stalks you selected will be pollinated by insects and eventually turn into a flower head full of seeds the next year. FYI, the seeds are black and small, resembling onion seeds.
The Seeds on the Stalk
- The leek seeds can be allowed to dry right on the stalk by simply leaving them there as the season progresses. The flower head will dry and turn papery. If you choose to dry on the stalk, watch the flower head carefully for signs that the dried flowers are opening.
- To prevent losing your seed to the ground while it dries, rubber band a lunch-sized paper bag over the flower head. If you have a muslin bag, you can use that, too. This will ensure that your seed will fall inside your bag while it dries on the plant, instead of onto the ground.
- If you live where rain will likely ruin the paper bag or cause rot inside a muslin one, cut the stalks and bring them inside when you notice the seeds are dark and the flowers have faded. Invert your cut stalks and place them, head first, into a paper bag to hang them in a well ventilated place to finish drying.
Do Leeks Grow Back Every Year?
Like I mentioned, leeks are biennial plants, meaning they live for two years. We usually grow them as annuals because we harvest them after only one year. They taste best this way.
When we want to save seed, though, we need to allow a few stalks to continue to grow into the second year. The leaves will become tough and bitter and you won’t want to eat them. However, they will produce wonderful seed heads!
Once the flowering heads open, the leek seeds (which look black pyramids) will drop to the ground if you don’t harvest all the seed in time. Pay attention, seed can ripen quickly!
If some seeds do fall to the ground and you live in a climate where they will survive the winter, new leeks will pop up in the spring without you having to plant them. This process is called self-sowing.
If you’re concerned that your weather is too cold (lower than zone 5), cover your leek bed with several inches of leaves or straw to over-winter. In the spring, pull that back and allow the new seeds to sprout and the old stalks to gather strength for the new growing season.
Cleaning the Leek Seeds
Back to the seed harvest!
OK, regardless of where you do it, once your seed is dry, you need to separate the chaff from your seed. Chaff is all the botanical mess that’s left behind as you separate seed from pods and flowers and stems.
Fortunately, with leeks, the seed is easy to see but there is a lot of loose chaff that comes off the seed head.
- Take each seed head one by one and rub them between your hands over a large bowl. Various plant parts will fall off into the bowl. Keep rubbing them to loosen all the stems and seed casing so the seed can pop out.
- Next either blow lightly to remove the chaff, or you can set a soft fan to blow on your bowl of seed/plant matter. Be patient, keep stirring the contents of your bowl and you’ll eventually get quite a bit of chaff out.
- I never get it all because I’m just not that detail oriented but if you want to, keep going until all the stems and loose material are blown out. Feel free to pick out large parts with your fingers.
- Use seed sifting screens if you want to get it “all”. This really isn’t necessary for the homestead seed-saver as it’s purely cosmetic. However, if you sell or trade your seed, you may want to do this extra step.
Store Clean Leek Seed
Store your cleaned leek seed in labeled paper envelopes (I use coin envelopes a lot). Place them in a cool, dark place and your seed should last one to two years.
I usually just replant another batch of leek seeds right away for the fall garden to overwinter. If I miss that step, I plant my stored leek seeds early, early the next spring indoors to put out for in the garden once the ground is workable.
If you do overwinter leek seeds in the garden, you may want to cover your leeks with something to insulate them during the coldest months. I’m in zone 5/6. My leeks have overwintered with both no cover and with a cover, and seem to do equally well. One winter we lost some when it dipped crazy cold, but I always plant more in my seed starting trays in February anyway.
If you plant leek seeds each spring, come late summer, you’ll have tasty leeks all ready to harvest again!
If saving seeds is your thing, try doing it with friends! Be sure to read the Seed Swap section of our book, The Do It Yourself Homestead. Don’t have your own copy? Click below to see what it’s about! If you’d like to read a sample from the book, just email me at Tessa@homesteadlady.com. Be sure to let me know it’s the Seed Swap section you’re interested in. With eight chapters of homesteading how-to’s and over 400 pages of homesteading information, there’s bound to be a lot that will interest you!
How to Use Leeks
Ah, recipes! Here are some links to leek-using recipes – you’re gonna love these!
Resources for Leeks
How To Clean Leeks (and What To Cook with Leeks)
Paleo & Keto Quiche with Smoked Salmon and Leeks
Leek and Zucchini Fritters
A Note on Kids and Seed Saving
Be sure to include your kids, grand-kids and even neighborhood kids in this great seed saving adventure! Passing on this gardening and homesteading lifestyle is a duty that doesn’t have to be laborious and serious all the time. Believe me, you’ll have a lot more fun if there are some kids around.
Yes, they may make a mess. It might take you longer and you might have to repeat some steps and instruction. These kids are the next generation of gardeners and do-it-yourselfers – they’re worth the time!
Just a thing to think about…
Want to Know More?
Remember to email me if you’d like a sample of the Seed Swap section from our book, The Do It Yourself Homestead. Find out why saving seed as a group might be important for your friends and neighbors. Learn how to easily put a group together or simply learn to share seeds you’ve saved in your area.
If you decide you’d like more, you can pick up a copy of The Do It Yourself Homestead on our website by clicking here. Here are a few words of praise from a fellow garden nerd and author, Stacy Lynn Harris:
Andrea says
Thank you so much for this detailed post. I had no idea leeks were so gorgeous when left to flower. I hope to grow leeks and save the seeds starting next year!
Homestead Lady says
You won’t be sorry! I hope it turns out well for you and that you make lots of yummy things.
Dianne says
thanks, good information
Homestead Lady says
You’re quite welcome, Dianne! I’m glad it was useful – I love saving Allium seeds. They’re so cute and round. Does that make me a seed nerd?
M j hockin says
I had 2 Leeks which came third place in a local competition. Replanted them. One died, however the other is now some 4 feet high and ready to flower. Your article is great! In a Greenhouse when is the best time to plant for next year’s competition. I live in the NE England. Any tips for growing….comp standard leeks. Girth, length of white trunk etc
Homestead Lady says
Congrats on your award winning leeks!
Typically you plant leeks 8-10 weeks before the last frost in your area. Depending on how well your greenhouse is insulated, you should be able to do that in there, but you’ll need to gauge the temperature yourself. Leeks do best germinating in cool temps (around 65 degrees) but you don’t want a severe dip in temps to stunt their growth. If you’re unsure, you can always start your leeks inside and then transplant them to the greenhouse as early spring starts to warm it. I’m not sure if your greenhouse is one you use only for starting plants, or if you’re talking about something more like a grow tunnel where you actually raise early spring crops, protected from frosts. Leeks are pretty hardy but they do need some warmth (not frozen ground and consistently frosty air) to develop.
If you want to grow them for competition, I suggest contacting your local extension agent and asking about standards for local fairs. Or, if the competition you mention is not a fair, contact the organizer directly. Every place has their own measuring stick, so to speak. We’ve used all kinds of things to keep long, white trunks with as little dirt as possible – our favorite was paper towel tubes placed over the stems to blanche them. We don’t use paper towels anymore so I need to come up with something similar. Toilet paper tubes worked, too, but we had a hard time keeping them connected and wet weather contorted their shape.
I actually prefer thinner leeks but those American Flags can get really fat. Hey, if its a leek, I’ll eat it – I love them!
Shannon says
I’m saving seed from carantan leeks in my garden right now. I was wondering if you’ve come across any plants wit more than one seed stalk before. One of mine actually has 3 flower stalks on it.
Homestead Lady says
Wow – you have an overachiever! If you’d like to send me a picture, I’ll put it in the post with credit back to your Ninja gardening skills. Just email me at tessa@homesteadlady.com, if you’d like.
Thanks for stopping by!
Deborah Kristensen says
Can I Ask you a question. . I had been saving the biggest leek to get my own seeds. But before I got around to harvesting it, it fell over onto the grass and started rotting – and sprouting! I picked up the rotting, sprouting head and started pulling out the baby leek plants, some only an inch high! And now I am trying to save them all! I brought in some soil, – it is still only the beginning of February- and am now trying to plant this little babies into soil in a little plastic container that grapes came in. Can you offer any advice??
Homestead Lady says
Wow – that was one determined mama plant! First of all, good for you for saving seed and saving back the genetic best. Sometimes life happens, though, and the garden has its own plans.
So, you should be able to keep the seedlings (the baby plants) alive without too much work. Leeks are alliums (related to onions) and alliums WANT to live, unlike some other seeds that seem determined to never sprout consistently!
You can use your grape container and some garden soil, if your garden soil is nice and loose. If it’s hard clay, you can add some compost and/or some garden soil purchase from the home store. Put soil into a large bowl and dampen it by mixing in some water with your hands. Squeeze the moistened soil in your fist and then open your hand to see if the soil has held together. If it holds together without leaking water down your arm, it’s perfect. If it falls apart immediately, add a little more water. If it leaks down your arm, add a little more soil.
Pack the soil into your container firmly but not so tightly that you can’t easily insert your finger into it. Smooth the surface. Using a bamboo skewer or your finger to make one small hole for each seedling. Set them in gently and tamp down the soil around them to keep them upright. Depending on how big they are, you may need to plant some a little deeper than others. If they’re taller, put them in a bit deeper. Keep them evenly moist and put them out when they’re at least four to six inches high.
If you still have the rotting seed head, you could plunk it into some dirt in a pot and see if anymore seedling emerge.
Did that help? Let me know if you need anything else or if I missed something.
JA says
I wish saving leeks seeds was as easy for me as you make it sound. I live in the Pacific Northwest and my overwintered leeks, the ones I saved to collect seed from, started sprouting flower stalks in April-June. Those flower heads got tall and large but didn’t open until July. We had tons of beautiful, huge flowers (they all ended up growing more than one flower) all summer that kept the bees happy but now it’s October and raining and the majority of seed is still green and immature. I picked a couple of heads that had a few black seeds and brought them in to dry and see what I can get but the amount of seed was a little underwhelming. I enjoyed the summer flowers so I am glad that I saved those leeks to go to seed instead of eating all of them. I just thought I’d share my experience saving leeks seeds in a different climate zone.
Homestead Lady says
All that water can be SO frustrating! Blessing and a curse, right? You can try growing your seed stock plants in containers, as opposed to in-ground. That way you can move them to a covered porch or other covered area to finish ripening. It’s an extra step and one more thing to remember to water when it’s dry, but it can mean the difference between a seed crop and no seed crop. You can also try a simple hoop structure over your seed plants – this allows the pollinators to still access them but keeps the rains off for the most part. Containers are probably easier for controlling soggy soils, but I have a hard time remembering container plants!
I hope that helps!
peterdempsey@europe.com says
I have some leeke growing in a flower patch, at least I think they are leeks each one has a seed pod on top of a long stem I need to see what the plant looks like before it opens into a flower a photo of a plant before would be nice
Homestead Lady says
That would be great if you did! The easiest thing to do to find a picture of a leek pre-seed-stalk is to google one or go onto the website where you bought the seed, if you can’t find the seed packet. Leeks have one, green stalk like a fat onion stalk – leeks and onions are from the same plant family, so they look very similar. Leeks are just bulkier in their stems.
Hope that helps!
Ewan says
Enjoyed the article however nothing mentioned about blanching leeks
Homestead Lady says
For more information on growing leeks – which would include blanching the leaves – I suggest this article: https://extension.umn.edu/vegetables/growing-leeks. Or, really any university extension article around the country (if you’re US based). You might also consider growing self-blanching leeks, if you don’t want to mess around with hilling or collaring your leeks.
Hope that helps!
Alvin Lamb says
Have let a few leeks go to seed here in Ireland this year – just in way of experiment. By the sound of it, they may be short of time to fully ripen before it gets too damp this autumn. The flowers really are beautiful – a lovely sight. From alvin
Homestead Lady says
A great experiment! Let them stay on the plant as long as you possibly can – ideally, until the surrounding white coat is dry and papery. If you can get them to that point, you can cut the stalks and bring them in to dry the rest of the way. Be sure to wrap their heads in a paper bag or pillow case to catch any seed that falls off as it dries.
You can do a germination test on your home-saved seeds to see if they’ll sprout. I so hope they do!
Chris Sames says
How can I use surplus seeds in the kitchen. Are they similar to onion seeds or Nigella?
Homestead Lady says
Great question! I’ve never read of any culinary uses of leek seeds BUT they are in the same family as onions. You might have to be an intrepid pioneer and experiment. If you do, let me know how it goes and I’ll add your info to the article!