How to Grow I’itoi Onions
In 2015 when I took the Master Gardener classes, they gave each student a couple of withered, sad-looking I’itoi onion bulbs. I was disappointed and thought, “There’s no way these will grow.”
I was wrong. Those of I’itoi onions have multiplied into thousands of bulbs that have since been eaten, planted, and shared with many others.
I’itoi onions tolerate and thrive in the Sonoran Desert’s difficult growing conditions. I’itoi onions (pronounced “EE-EE-toy”) have a long history in the Sonoran Desert. According to legend, I’itoi – the creator of the O’odham people – called his people together and presented them with onions to plant and share. Learn how to grow I’itoi onions with these tips.
9 Tips for How to Grow I’itoi Onions
1. Find bulbs to plant I’itoi onions
Some years, it is hard to know where to buy I’itoi onions. They can be challenging to come by. In other years, it’s easy to find them at the farmer’s market or other local sellers. Check Native Seeds Search or Crooked Sky Farm, as they may have them available for purchase.
If you’re having a hard time finding I’itoi onion bulbs to plant, ask other gardeners – they may have some to share.
Occasionally, I have them available in my shop. You can check here to see if I have them in stock.
2. Understand how I’itoi onions grow
I’itoi onions are a multiplier onion (allium cepa var. Aggregatum). The planted onion multiplies and is propagated by the division of bulbs.
From just a single bulb, the magic of nature unfolds. Plant it once, and it multiplies into 8 or 10 (or even more) bulbs. Once harvested, each of those bulbs can be divided and planted, resulting in another extraordinary multiplication. Behold the astonishment as 1-2 onions, within a span of only a couple of seasons, transform into a bountiful harvest of hundreds.
3. Plant and care for I’itoi onions correctly
When to plant I’itoi onions
In cold winter areas, plant I’itoi onions in the spring.
In the low desert of Arizona, I’itoi onions are normally planted with the monsoon moisture in August; continue planting through November. However, this tough, easy-to-grow onion can probably be planted successfully most times of the year.
How to plant I’itoi onions
I keep the clump of bulbs together until I’m ready to plant, just like garlic. Once I’m prepared to plant, I carefully separate each bulb and plant them individually.
To ensure optimal growth, plant each bulb approximately 1 inch (2.54 cm) deep, spacing them 6-8 inches (15-20 cm) apart. For square-foot gardening, place four bulbs within each square.
Where to plant I’itoi onions
I’itoi onions will grow in native soil, requiring no additional feeding. Nevertheless, richer soil yields a more abundant harvest of larger bulbs and shoots. I grow my I’itoi onions in raised beds with the Raised Bed Mix from Arizona Worm Farm. The rich soil produces large bulbs and plentiful greens.
I’itoi onions grow well in containers and can be tucked in almost anywhere in your garden.
Choose an area with plenty of sunlight if possible. They tolerate shady conditions, but the bulbs will be smaller. I’itoi onions can be grown in full sun. They normally die back and are dormant if left in the ground during the hottest parts of summer.
How to care for I’itoi onions
I’itoi onions tolerate dry conditions and will respond to monsoons and other rains with growth. Just as with amendments to the soil, regular watering produces larger bulbs and shoots.
Once these onions are planted, they thrive effortlessly and require minimal care. Pest and disease problems are uncommon, allowing for a worry-free growing experience.
Occasionally, I’itoi onions will bolt and flower. The bolted onions will not store as well and should be used right away. While I’itoi onions are typically cultivated from bulbs, if seeds are allowed to develop on the flowers, they can be used for planting. My experience with growing I’itoi onions from seeds has yielded varying degrees of success.
4. Plant I’itoi onions as companion plants
Because I’itoi onions are easy to grow, it is simple to plant them throughout the garden. Onions are excellent companion plants for brassicas, beets, strawberries, and tomatoes.
By planting a single bulb in close proximity to the plant, the I’itoi onions will flourish, multiply, and offer valuable companion planting advantages. For more information on preventing pests organically, read this post.
I’itoi onions help repel common cucumber pests. See what else you can plant near cucumbers in this comprehensive cucumber companion planting guide.
5. Use all parts of the I’itoi onion as needed throughout the season
As green shoots develop, harvest as needed by trimming them off the onion. The greens have a mild flavor and work well in most recipes that call for chives or green onions. The onion will regrow new shoots.
Harvest individual bulbs as needed throughout the growing season. To harvest individual bulbs off of the clump, carefully dig down until you see the base of the onion. Pull off as many onions as needed, and then push the soil back around the remaining onions.
To use the bulb, wash and peel. The bulbs have a mild, peppery flavor similar to shallots. They are delicious sautéed and in recipes that call for shallots or onions.
6. Harvest I’itoi onions at the right time
The best time to harvest I’itoi onions depends on what you are using them for.
For fresh eating, harvest the greens or bulbs anytime throughout the growing season.
For the largest bulbs, allow the greens to die back and then harvest. The bulbs develop a papery skin. In the low desert of Arizona, I’itoi onions are usually ready for harvest between May and July.
Onions that are harvested when the stalks are still green can still be cured, but it takes longer, and the bulbs will be smaller.
If desired, you can leave the bulbs in the ground after the greens die back. They will go somewhat dormant over the summer and then begin growing again in early fall.
Pull up clumps of onions and allow them to cure for the most extended storage life. Onions may rot and mold if not cured and stored correctly.
Although you can leave them in the ground, I prefer to harvest, cure, divide, and replant the onions with the monsoon moisture. The onions will multiply much more if harvested and replanted separately rather than staying in one large clump.
7. Cure I’itoi onions before storing
How to cure I’itoi onions:
- Choose a shady location around 75-80°F (24-27°C). Provide a slight breeze with a fan if possible if it is indoors.
- Lay the onions out on a rack or floor.
- Cure until the onion stems wither and the papery skins tighten around the onions. The dried stems will slip easily from the onion when they are done curing.
I cure my I’itoi onions in racks inside this repurposed dresser-turned-potting table.
8. Store cured I’itoi onions correctly
Store cured I’itoi onions in a dry, cool place. A great way to store onions is in mesh net bags (I use these mesh bags from Amazon) hung up in a cool closet. The onions must have good airflow, or they will get moldy.
Check stored onions regularly, and discard (or plant right away) soft or moldy onions.
9. Enjoy, save, and share I’itoi onions
Whenever you harvest I’itoi onions, make sure to enjoy a portion, set aside some for planting, and generously share the rest with fellow onion enthusiasts. Let the goodness grow and spread!
If this post about how to grow I’itoi onions was helpful, please share it:
Like to give a try to grow I’Itoi onions.Thank you for sharing.
They are a great easy-to-grow addition to a garden. Thanks for commenting!
For many years (about 30), I have been looking for the multiplying onions my grandma and a great aunt used to grow in east Texas in the Houston area. They *never* bloomed and never went dormant. I think I’ve figured out they were actually shallots; a variety called “Louisiana Evergreen”, which I can’t find anywhere.
I recently bought some no-name multiplying onions off eBay that look and smell like I remember, except these were dormant when I received them. (they sprouted immediately when I planted them) We’ll see if they are close to what I remember.
I have also planted a few ping pong ball sized shallots I bought at an Asian market. They also look and smell right, but they are not multiplying like the ones I remember. They multiplied once, but then it doesn’t look like the new bulblets keep dividing. They are making real bulbs instead and will then probably go dormant. They are also producing scapes (flower stalks) but don’t seem to be putting much energy into them so that’s okay, but it’s an indicator they are not the same as what I’m looking for.
[Finally getting to the point] I live in southern Minnesota now; the south end of zone 4. Would I’Itoi onions survive the cold up here if I keep them covered with leaves and snow in the winter for protection? Can they be lifted and stored for 5 months and then planted in the spring? (yes, winters are 5 months long here) Thanks.
Not sure about surviving the cold outside… but I think they would be fine if you brought them in and stored them inside. Be sure to store them in a paper sack or something that breathes. Best of luck. Let me know how it goes. I’d love to know how they do in cold climates.
I tried growing I’itoi in Vermont over the past year. They did fairly well over last summer and fall, but all of the I’itoi bulbs I left in the ground failed to sprout this year. Even the ones protected in cold frames did not sprout.
Oddly, the I’itoi I pulled last fall and stored in the house over the winter completely dried out, turning to nothing but paper skins with no bulb remaining. I replanted them, but they appear to be dead.
So I lost three-quarters of my I’itoi. The only ones remaining were grown in the house under grow lights all winter. They flourished, with one bulb becoming eight!
I wish there was more information out there on growing I’itoi in climates other than the Desert Southwest.
Interesting. Thanks for sharing your feedback. Each climate is so different. I’m sorry about the loss of some of your onions, but glad a few survived. Please keep me posted as you continue learning about growing them in your climate.
I’m from Australia and I grow what I call shallots. They are so so close to what you call I’itoi onions. I can grow these all year if I want to eat the shallot/onion raw (like chopped on a sandwich, raw by it’s self in a salad, chopped into scrambled eggs or tossed salad. If I want to produce bulbs then I plant early autumn and then again spring into summer and even during summer. In the cooler weather of winter (5-14 night to 20-25 day degrees Celsius) they are slow to form bulbs or no bulb. In the warmer to hot weather (19-24 night and 28-35 day degrees C ) form bulbs very quickly. When dried out they will only last so long before they dry out and then they will not shoot and grow. So you need to plant them before they dry out. Also they will start shooting in certain conditions (I think when it is humid). The ones I harvested in Feb (late summer) have start shooting a month ago (mid winter). Mine do produce a seed head although I have never tried to grow from seed. I have grown and used the bulbs from year to year for 40 years. I sell quite a few bulbs to Asian and Indian women who use them in curries and sauces.
I plant 2-3 bulbs together and recently I pulled a bunch out (mid winter) it had 76 stalks. You can actually pull a bunch out before they bulb and replant some of the stalks. Make them about 4-6″ long and leave the top half out of the ground. They will shoot and multiply. I grow mine in Sub Tropical Queensland Australia. Cool dryish winters 5-14 nights 20-25 day degree C — warm to hot wet summers 18-24 night and 30-35 day. You could grow in any climate zone, just need to work out what season/s. Plenty of fertiliser to make them produce big bulbs. Read the other comments I have put here today.
@RobertB, according to Strictly Medicinal Seeds, https://strictlymedicinalseeds.com/product/onion-iitoi-multiplying-onion-potted-plant/
I’itoi multiplying onions are hardy perennials in zones 3-12.
If planting in the fall in the low desert, about how long or what time of year until the greens die and they are ready for harvest? Is there an ideal environment to save the bulbs for next season, i.e. in the fridge or dark pantry?
This can be anywhere from April – August depending on where they are planted. The bulbs do mold very easily so keeping them cool and dry is important. The fridge or dark pantry would work, be sure there is plenty of airflow so they don’t get moldy.
When they have formed big bulbs the tops will usually fall over and start to die. You can pull them out of the ground and leave them lay on the soil for a few days to a week (not if there is rain happening). Then trim the top and most roots off and lay in a flat tray only about 2″ deep. I use the trays (1’x1′)seedling punnets come in or trays that small pot plants come in – 2′ x 2.5′. I leave these out in a shaded area for another week or so and then store them in my shed. Do not pack them tight together – they will rot. Generally shallots take 12-16 weeks to grow and form bulbs.
What should be done if the start to flower?
I haven’t had them flower before. You can let them flower and save the seeds. Or if harvest and eat soon, they won’t store well once they bolt.
If they flower don’t worry about it, let them die back then harvest them and let dry and store them to eat or for planting next year.
@Susan Spaulding, I had mine flower for the first time this year. I had heard that they do not sprout from seeds, so not sure if it is worth trying to save them for reseeding purposes. That could be wrong info though.
I pulled mine before the blooms could pop open and they are being cured on a shelf. I am not sure what caused the bolting, other than the crazy winter weather that we had here in the Phoenix area!
Hi Angela!
First of all, thank you for all your hard work – it is greatly appreciated! Would really love to try growing these, but it looks like Native Seed Search is no longer selling these. Do you know of another source?
Hi Angela!
First of all, thank you for all your hard work – it’s much appreciated!
I was wondering if there was another source for bulbs. Native Seed Search is apparently no longer selling these to the general public…
Hi Summer. I had a great harvest this year and hope to add them for sale on my website once they are cured.
Are these available for sale? I’d love to plant some for monsoon season.
They are difficult to find for sale. Keep an eye out with local growers, nurseries, etc.
I’m in Tempe; I was wondering if you had them available yet?
I don’t, sorry. Vilardi Gardens (online and at local markets) has some I believe.
Hi Angela,
Love your blogs, thanks for sharing lots of great information. I am ordering so I”itoi onions from the nursery you posted today (thank you)! I am unclear on how to save onions for next year planting? Do I leave them in the ground? Do I cure them?
They will multiply in the ground. At the end of the season pull them out and cure them – then plant again the next season.
How do you harvest an individual bulb without disturbing the cluster?
Carefully – I just dig around it a bit and pull one or two off.
Hi Angela.
A couple of my clusters have put up two or three flowers. I know it’s early but should I go ahead and pull them out and cure them? Typically how long is the curing process?
Question #2 about garlic.
My garlic is huge. I’ve pulled out a couple of heads and have them curing. Is it too early to pull the rest? The bottom leaves are brown and the bulbs that I’ve pulled are the size of my palm. This is my first time growing onion’s and garlic so I’m not sure how to proceed. I’m in Queen Creek.
Hi Terri, If onions bolt they won’t store well and should be used right away. You can also leave them in the ground and let them set seed. As for your garlic, it sounds like it’s ready to harvest. Congrats!
Hi Angela,
I finally found some I’itoi onion plants today at a farmer’s market. I know these are usually planted later in the year, but I’m wondering if I would be fine planting them now in April?
Sure, you can always give them a try and see how they do.
Where can the planting bulbs be found? I would love to try them out – am in the Tucson area and I am trying to incorporate “local” veg & flowers in my garden.
They can be tough to find. Check local farmer’s markets. Villardi Garden’s here in the Phoenix Metro area has them occasionally. You could also check with Native Seed Search.
@Rebecca, Mine came from Spadefoot Nursery, on Broadway.
In the Green Valley area (south of Tucson) I have been wondering where I can find the I’itoi onion starts. Do you have a reliable on-line nursery you buy them from or can you or any of your followers suggest somewhere to find them? It is May right now – when should I be looking to plant these outside? Should I consider the timing of planting as if they were shallots? Thanks for any info!
Unfortunately, no I don’t have a source. I like to plant mine out with the monsoons in August through October or November.
@Rebecca, native seeds search sells them now.
@Rebecca,
I would be happy to sell you some. We have an abundance.
Hi Angela, So happy to have found another Arizona grower! Your videos are a huge help! One of your comments below say you will have some I’itoi Onions available for sale on your website when cured. Are they for sale yet, I cant find them.
I had some to sell in previous years, but I don’t currently have any for sale.
@Angela Judd,
Hi Angela,
In April 2020 I was able to purchase some I’itoi onions from Crooked Sky Farms in Phoenix. Perhaps that will help your interested viewers.
Crooked Sky Farms
Main: 623-363-7422
Hours of Operation: Mon-Fri 8:00 a.m. – 12:00 p.m.
Location: 2615 S. 27th Ave. Phoenix, AZ 85009
(I have no affiliation with Crooked Sky, BTW).
I enjoy your web site. It is especially relevant as I am in Chandler.
Best,
Ed Bawolek
Thank you!
@Raejean,
@Angela Judd,
We are in East Mesa. We have an abundance right now. Happy to sell some.
@Susan Spaulding,
We have an abundance. We are in East mesa.
Hi Angela,
Native-Seeds-Search has I’itoi onions for sale on their website today if any are interested in buying them.
Best,
Tricia
Thanks for the heads up. I shared it on a couple of my social channels.
Hi Angela, a question about I’itoi onions, can they be kept in refrigerator until ready to plant in colder regions?
That should be fine.
Where can we purchase these onions?
Check online at Native Seeds or Crooked Sky Farms they often carry them seasonally.
@Cindy, the Chandler Nature Center should start to have some in their free seed cabinet sometime in mid to late August. You can always give the front desk a call to see if there are any in stock (the phone number comes up correctly when you google our name). We had a box of them generously donated to us a few years ago and love to give back to the community when we have extra! And we probably had close to 800ish onions this year. 🙂
I have been growing I’itoi for about 8 years here in central AZ. They are the best as a scallion, or shallot, or even chives. We have 4 seasons here ……………… 20’s in the winter and 110’s in the summer. The I’toi tolerate the extremes quite well. I grow them year round and replant anytime, as long as the soil isn’t frozen.
Now here’s a tip ………… when you cut the roots off when prepping for dinner, save the roots and replant. Seriously, they will grow into a bunch of 30-40 scallions. Oh! Check out potato onions. 🙂
Great tips from a longtime grower. Thank you!!!
Grew them this last year – loved it! Used your tips but I have one question..
when trimming the i’itoi onions to use how far down should I cut them to keep them growing and producing? There is a natural ‘Y’ in the stem growth it seems – should I trim below that or above? Or right down to the ground?
@Rebecca,
I assume by trim that you’re referring to harvesting the green tops while leaving the remainder of the onion in the ground to continue growing; what my elders always called “cut and come again” plantings.
I recently acquired some I’itoi sets from a seller on Etsy and this is my first attempt at growing these specifically, however, I have grown others and in my experience you can cut them quite short. I typically cut the tops down to within 1/2″ -1″ above the ground for immediate use when I need scallions/green onions and they remainder left behind have never failed to resprout and grow new green tops.
I hope this answers your question.
Thanks for this great info about I’itoi onions. I had never heard of them until about a year ago when a friend gave me some. I’m hooked! These are amazing and I prefer them over the regular green onions like are bought in the store. Thanks for sharing your expertise to help us become better gardeners!
So glad you have some! Finding them is the hardest part about growing this amazing crop!