There's been a lamentable loss of potato onion varieties over the past century, such that old heirlooms are now incredibly hard to come by. This project hopes to help bring that diversity back.
80031
United States
25, Oct, 2025 Started a 98 tray of seeds as soon as I received them. I purchased 2 packets of Lot #AGMM0-NR-23 (40seeds/packet)
27, Oct 2025 Starting another 98 tray with the remaining seeds
I purchased some Green Mountain Multiplier seeds from EFN this winter. Planted 100 seeds in February and raised the plants in nursery conditions for about 2 months. They were transplanted in a large raised bed alongside cabbage, asparagus, scallions, marigold, and calendula. We had about a 40% success rate from seeding to mature plants. Our June and July were fairly dry and the plants needed watering 1-2 a week. By August we got more rainy and cool weather which continued into September.
About 15 plants have visible bulbs, some of which were harvested and eaten fresh. The bulbs were all white, most were a single large bulb however a few plants split and produced two small bulbs.
About 10 plants bolted and produced seeds. From doing some online research, this isn't common and was likely caused by some form of stress, potentially too little water during the early summer. I harvested about 200 seeds from those plants and plan to germinate them next year. These plants are in the same bed as some scallions ('Flagpole' variety), though I don't believe that the two crops interbred as the scallions were regularly trimmed.
Over half the plants have not flowered or produced a visible bulb. They look more like a green onion but tend to have a thicker stalk. They haven't produced a blub above or below ground.
Because of our short growing season, the plants have not died back to allow the curing process to start. With frost in the forecast and the ground normally frozen by November 1, I plan to leave the plants in the ground and heavily mulch them with compost and leaves. Our winters are borderline zone 4, so the hope is with heavy mulch, some plants will survive the winter. Because of our short growing season, I think this will give them the best chance to grow and divide next summer.
I am willing to participate if you let me know how.
I have been planting potato onions since 2020 that were originally purchased from SESE. During 2024 I expanded the genetics by adding lines from Filaree and a generational variety from the Appalachian Mountains. Fall 2024 I will also be planting five bulbs that originated in Black Isle of the Scottish Highlands.
If anyone has varieties other than those listed, I would be interested in buying/trading.
For more information about me https:/www.potatoonionguy.com or https://www.youtube.com/@PotatoOnionGuy
This is a follow on to my previous posts. Last summer, I let all of Andy's Green Mountain Multiplier Onions go to seed. I kept some in isolation from any other onions and those did produce fertile seed. I planted some of these seeds in the fall to try overwintering the young plants under row cover. As of mid-January the plants were still growing well. I would like to see if they will form bulbs this summer, or if they will go directly to seed. I have noticed that the EFN store is already sold out of seed. After cleaning and processing my seed, it looks like I have more seed than I will be able to grow out myself this year, so if anyone is interested in getting some, please email me and we can work out the details offline.
-Robert
rmichell145@gmail.com
This is a follow on to my previous posts. Last fall, I planted the Andy's Green Mountain Multiplier bulbs I had grown from seed in 2022 and most of them sent up seed stalks in the spring. Most of them also produced either a single bulb or a double bulb next to the seed stalk. See photo of the bulbs I was able to harvest (mostly 1 to 2 inches in diameter). We had a really dry spring and then a wet early summer, so all on my onions did really poorly, including these. I plan to replant these this fall and see how they do, but they do not seem to divide a lot, mostly singles and doubles. I have some seeds from some of these that were flowering at the same time as some Ed's Red Shallot nearby, so it is possible that they could have crossed. I don't have a lot of these seeds to share, but if anyone is interested in trying to grow some out, please email me to work out the details. rmichell145@gmail.com.
First time growing out true potato onion seed this past year. Seeds were from EFN and were half yellow, half white. Most of the bulbs I harvested were too small or immature and didn't cure well so have rotted. (I'm still figuring out how to grow onions successfully.) But this one still looked good and I threw it in a pot a couple weeks ago to at least ensure I could keep it alive for season #2.
From this early sprouting, it looks like 3 separate leaf sections are coming up. Am I correct in assuming that means 3 bulbs will develop this next season? This seems like it might be useful in screening for division traits... start first year bulbs inside, and if you only have one stem, yank it and eat what's not yet become baby plant food, otherwise transplant out the onions you know will divide.
The result of growing green mountain potato onion from seed that flowered at the same time right next to a very large sized ordinary onion. Could one of them turn out to be a larger-bulbed variety? All smallish brown ones and there are more are the result of a mass sowing from seeds of 25 different accessions from a genebank.
No extraordinary differences in size came from the growout of the genebank seeds.
No huge increase in size when growing out the genebank seeds was noticed.
But an increase in size did happen with this years green mountain x large onion seed.
To be seen whether these white ones will continue to give larger onions and how they will divide.
Hi All,
I have been following the limited research around Potato Onions for some time now and have just re-joined the EFN conversation on this. There has been so much information online about common names that we call plants and limited information about the species that the plant may or may not be in the past, but it seems as though we have caught up a bit on the Potato Onion conversation. I first grew Potato Onions three years ago which were called Multiplier Onions to me and once I grew them out, I realized they were different. I am a huge fan of the Allium fistulosum which is my understanding of an evergreen multiplying onion as well as the different chives that are out there due to their similar growth habit. However, Potato Onions are on another level and it is my hope to begin stewarding different cultivars of this species.
I am hoping to connect with other here to acquire additional knowledge and growing considerations as I begin to build a stock of plants and seed to grow out in the upcoming 2023 season. If you have any suggestions or additional stock to share or would like to connect directly about growing Potato Onions, especially in the PNW you can email me directly at jamesm@ctsi.nsn.us
Thank you all and hope to hear back soon!
-Zeph
Photo shows two crates showing a representative sample of my 2022 potato onion harvest. I harvested approximately 80 pounds of onions this year as well as a goodly amount of true seed. The diversity of my collection is improving at an increasing rate each year.
This 2022 growing season had a lengthy dry spell that adversely affected size of the potato onion bulbs, though general bulb quality for winter storage is excellent. Dry spells are a double edged sword, but I would take dry spells over too much seasonal rainfall any time.
On average approximately 10% of my crop flowers and produces seeds every year now. I consider this a very acceptable rate so I can get onions for planting as well as for food production and also get a decent amount of true seed to continue rapid development of the collection.
On October 01, 2022 I fall-planted approximately 450 potato onion sets for the 2023 season. I plan on planting 500-750 sets next spring as well as around 500 transplants I start indoors from true seed.
I wish this and all EFN projects were more active. These projects are the right idea but lacking in the capability for members to engage in discussion. I believe this issue will continue to cause minimal involvement and lack of interest in these potentially valuable projects.
Some more info and pictures on my blog: permabreed.blogspot.com (select potato onions - top left)
Hello,
I am just after joining the experimental farm network/ potato onion project.
My name is Philip. I live in brittany, france.
I planted about 50 potato onion bulbs grown from seed this year.
The bulbs were selected from about 300 seed grown potato onions.
The seeds came from 25 different accessions of the nordgen genebank in europe.
They consisted of mainly scandinavian and eastern european accessions of potato onions, but also other european countries.
So all of my 50 or so plants are genetically different.
I am on a quest to try and breed potato onions that are larger.
None of these seed grown plants seem to show any extraordinary genetics in terms of size, so they don't actually interest me that much anymore.
For people, however, who want to save and even improve genetic diversity of potato onions these plants could be of great value.
Obtaining these seeds as a private person from the genebank was very difficult and expensive.
I basically selected the 50 plants out of the 300 for size and least amount of dividing (being convinced they shouldn't divide in their first year grown from seed)
This year was a very dry year and the potato onions grew very poorly.
I didn't have time to water them.
I have gone down the path of trying to cross potato onions with large size ordinary onions hoping to improve potato onion size that way.
I grew a batch of green mountain x large onion seeds this year that were all white and much bigger than the nests of the 50 bulbs i had selected from last year and that divided for the first time this year.
I will probably try and multiply all the seed grown types from the seedbanks' seed and grow them under normal conditions to better evaluate and share them.
Like I said they don't interest me that much anymore but represent a much wider genetic diversity than the handful of varieties circulating in the usa from what i know.
Kelly Winterton bred many new varieties from seeds of his original strain and a few other varieties were found but i get the impression that genetic diversity of potato onions in america is still rather low.
Am i wrong?
I was very surprised when I found 30+ accessions of potato onions from different countries in europe in the nordgen genebank and thrilled when I received 25 different accessions.
They all turned out to be potato onions.
There is many different colours, but i didn't get the large bulbed plants i was hoping for.
Conditions were very poor this year though.
I was already going to drop them and forget about them but it seems like a huge waste and pity if people here are interested in potato onion diversity.
This is a follow-up to my previous post (27 July 2022). I grew out some of the multiplier onion seeds that I got from EFN this spring. They did well, I ended up getting around 50 bulbs. I plan to re-plant about half of these. The other half I am happy to share with members of the group here. If interested, please email me separately to work out the details: rmichell145@gmail.com
There appears to be three main morphologies (tan skin, reddish skin and white skin) see photos below. Some of them formed multiple bulbs the first year, many just formed single bulbs. A few of the single bulbs were quite large (>2 inches in diameter).
This is a follow up post to my October 2021 post. Of the 8 bulbs that I planted in the fall of 2021, 4 plants survived all the way to summer 2022, producing 8 bulbs total. All of the plants produced flower stalks in the late spring, which I removed when they were young, to get better bulb growth.
One plant produced 5 individual bulbs, centered around a central flower stalk. Three plants produced single bulbs next to a flower stalk. See photos. I plan to plant all of these this fall, keeping track of which ones were from the plant that produced the five bulbs.
Also, this spring I was able to get some new seed from Experimental Farm Network, which I grew out. These did rather well this year. I will post another update about these later this summer, when they are done drying down. I anticipate having enough bulbs that I should be able to share some with interested members. I'll post more details about this a little later this summer. Stay tuned.
ok. I have 5 remaining plants. 2 of them have been transplanted to a different location. The 3 remain in the semi-protected hoop house and have flower stalks. That's all. I did collect some seeds last year.
All of my surviving 3rd year potato onions are flowering. This is the same thing that happened with the onions in their second year (100% of survivors flowered). I was under the impression that by the 3rd year some of them would not be flowering and would simply divide. The flower stalk prevents the onion from bulbing up much like they did in the first year. Can someone with more experience comment on how many years of replanting until the flowering starts to subside? Is there any difference in flowering and dividing behavior when overwintering in the ground vs overwintering in dry storage? Thank you!
Hi everybody,
All the potato onion true seed that I have has been spoken for. As soon as I receive a SASE from those who have contacted me, it will be in the mail.
Happy gardening
Hi all
I posted earlier that I do have some true seeds for potato onions. I have gotten a couple of emails saying someone has commented about getting seed, but when I come to this site I don't see anything as far as comments. I would like to connect with those who would like seed. I want it get it to folks who will grow it out. Would want to to send me a stamped, self addressed envelope and I will send it back with seeds. Please email me at fts@haunhaus.org. Wish there were a way to do a private message on this site.
chonas009@hotmail.com. we can work out shipping details for a small amount of seeds?
