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onion blooming for seed



Four decades of Growing Good Food in Michigan's Upper Peninsula
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What a generous crop onions are in their many splendid faces and moods. Hardly a meal goes by without some form of onion involved (excepting breakfast - no onions in the oatmeal). I grow them, we eat them, the pollinators love the flowering seed onions, and they're a constant in the garden all year long. 

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 September 6, 2021 -- Onions for all Occasions      

harvested onions  2021We eat quite a lot of onions - small ones in luncheon salads, larger ones in a variety of dinner dishes, tiny ones to save and plant next year as onion sets, any size diced up with sweet peppers and fermented into a delicious relish. My seed is an open-pollinated mix that I've been growing and saving for decades, aiming for that sweet spot of medium size that is just right for one meal. And some years I get a lot that size, some years more smalls, and some years more large. My onions are very independent.

And this year they decided to make great use of this (rare? or now common?) hot summer and go for large, as in three-meals worth sized (in the left crate). Even the mediums are on the hefty size. Like most things in the garden they matured early so were harvested 2-3 weeks ago. So they've been curing under cover, waiting for that perfect nice day when it felt great to sit outside in the sun and clean the beautiful bulbs for storage. And this was the day. It was a very good harvest, and much appreciated.

Onions are truly a year round crop for me. One of the last to be planted outside in the fall they are also one of the first to be planted inside in the spring. And most years they are fresh for the eating all twelve months, if one allows stored roots as being fresh. Once planted they demand little in the way of fussing which makes them a little too easy to overlook when extra attention is needed. But they are hardy souls and usually pull through in spite of the gardener or the weather.

This doesn’t mean one can just ignore them and get a good crop. They have their requirements and preferences and are known to withhold their favors if the basics aren’t met. But in general they are easy to grow and harvest, and seldom is a day that they aren’t a part of at least one meal for us, usually two. Considering that so many of the inhabitants of my garden tend to excessive complaints about the cold and short season, the hardy onions are a welcome companion.

Onions come in many styles, flavors and habits and it is this diversity that allows “year-round” designation for me. If you add in other Alliums such as leeks, scallions, shallots, garlic and chives you can have a large choice and a large garden of wonderfully (for those who are fond of that flavor) tasty additions for the pot and table. I grow 'regular' storage onions, potato onions, green onions, garlic, chives and 'for seed' onions. The regular bulb onions are my main crop, used in so many different ways. But success all starts with...

SOIL -- My garden soil is sandy loam built up over the years by the plants that grow there and hay mulch that is added, with a little compost from the bin here and there, maybe some wood ashes. Plus whatever is contributed by the snow and rain and wind (which I think is more than is usually given credit for). It grows good crops including the onions.

WEEDS -- There are some vegetables that can handle weedy companions and some that can’t. Onions are staunch individualists (at least mine are). They don’t demand a lot of space but what they have they prefer to inhabit it by themselves. One of my first learn-by-experience garden lessons was with a weedy patch of onions (actually, the entire garden was full of weeds that year). These were the generic purchased commercial yellow onion sets which are generally hardy and able to overcome many gardener errors. And they did grow. And I did get around to weeding the plot eventually, maybe mid-summer. The onions weren’t real happy but they came through and made a reasonable crop but the bulbs were small. I was happy to have any at all. And when I cut open one of those nicely matured and cured bulbs I discovered that they contained all of the fire that is usually spread out throughout a much larger bulb area. I wiped my eyes and was still happy to have them, but no nibbling raw pieces that year. Whew! Maybe it was the hot summer not the weeds but I vowed not to not crowd the onions in the future. And though I never had such a badly overgrown onion patch again, subsequent years have confirmed that they like their space and resent intruders, whether it be encroaching weeds, other garden plants or other onions.

PLANTING -- So it is with spacing of the plants. Mine seem to like to be 5” apart. They could be a bit more or less but my five foot long “planting dibble” has dowels set every 5” and that spacing works well. Since I plant in wide rows (permanent beds in my case) that spacing is both along and across the beds, and is used for all my main crop onions as well as garlic. When to plant depends on what I want and what I’m planting (seed, sets, plants) but most onions are planted in early spring for fall harvest. Onions like the sun so are planted in a sunny bed.

REGULAR ONIONS -- Which in my case means onions that grow from seed. My onion seed is a cross of various short season open pollinated (OP) storage onions which have been available from the independent seedmen over the years. We aren’t in the best onion from seed and onion seed growing area; they generally prefer a longer season. I’ve experimented with many varieties, hybrid and OP. My requirements limited my selection and what got to continue. I wanted onions that were (1) good keepers, (2) would grow bulbs of a reasonable size without too many thicknecks in a normal growing season, and (3) would grow and set viable seed the second year. It turned out the yellow onion varieties were the best though there's still a few reds in my mix. I’ve been growing, crossing (or rather allowing to cross) and selecting for thirty years so my seed is pretty well adapted now to our climate and my garden.

But there are good onions to be had from the seedmen. If you aren’t going to grow your own seed it doesn’t matter if you grow hybrid or open-pollinated seed. Fedco Seeds offers a good selection of varieties for the short season gardener as do many other of the independent seed companies. Onion seed is one of the few that doesn’t remain viable for very long. It depends on the quality of the seed but I figure three years, four years is pushing it, seldom will they germinate after that. It’s easy to do a germination test of a couple dozen seeds ahead of time if in doubt. But I simply plant and make note how each year’s seed (or each variety) germinates when I plant them, then I know for the next year. If the germination is poor I toss the seed, if it’s just OK but not “very good” I plant thicker the next (probably last) year. The seed doesn’t just completely give out suddenly one year so it’s not an all or nothing scene, but it does go downhill after a few years.

DIRECT SPRING SEEDING -- Even the earliest maturing onion seed will seldom make a good crop when planted directly in my garden in early spring but that doesn’t keep me from trying. They grow fine for salad onions when young and certainly edible later even if they don’t get large. If I have extra seed and extra space, and I remember (they do have to be planted early), I might plant a small plot of seed. Sometimes Nature treats me and the onions well and I get a reasonably good crop, though they are always smaller bulbs than those from plants or sets. I plant in rows about 5” apart, thinning within the row to 3-5” apart.

DIRECT SEEDING OVERWINTERED -- This is experimental for me but I’ve planted seed in late spring/early summer and left them to grow to overwinter. Success varies depending on the weather, but it’s easy and if they make it so much the better. A light mulch in the fall may help them through cold times when the snow comes late or is sparse. But too much mulch makes for too tender plants which are susceptible to damage by spring frosts and freezes. They start growing very early in the spring so pull extra mulch away early. If temps plummet throw the mulch back over them. In years of good snow, mulch wouldn’t be so important and they seem to come through hardier. But it’s hard to guess in the fall how much snow we’ll have. Before they get too large in the spring I transplant them out to 5”. Or you could just thin them where they are to that spacing. This is easier than starting the plants inside but not as reliable for our zone. These plants are more likely to want to set a seed head and to form double bulbs but they’re great for early fresh eating and the seed heads are easily nipped off. They mature earlier than the greenhouse started plants which is nice for summer harvest.

Of course, many times onions are overwintered successfully in the garden on their own without any help or hindrance from me. Small onions in the main crop that are overlooked or ignored at harvest time often grow up in the spring. I used to “weed” them out, now I let them grow or transplant them to a better spot, using them as an early green onion or larger bulb onion later as above. They are a reminder that I’m apt to make gardening more complicated and difficult than it needs to be!

PLANTS -- My main crop is started early in the greenhouse. In March when the weather warms a bit, I get that winter’s-winding-down feel, it’s maple sap time, and I just feel like planting something. It’s time to start the onions and peppers. I plant the seed not too thickly in flats, rows an inch or two apart, keeping the different years (or varieties) separate. They usually start inside near the woodstove until they’re up then they move out to the greenhouse. They’re hardy and don’t mind the cool room. The biggest chore is to thin them to a reasonable spacing as they grow, a half inch apart would be good, or so I keep telling myself. They do MUCH BETTER when not crowded. But they look so small it’s hard to convince myself that they do indeed grow and want their space. I also keep the tops trimmed down to maybe four inches. It makes for sturdier plants at transplanting time and less of a tangle. Overall onions are one of my least fussy plants in the greenhouse.

onion plantsThey simply grow and when the weather has settled some outside they’re ready to go. Because we often get early spring dips into the teens I’ve learned to be patient and not set the onions out too early, usually end of May/first of June. Once they’re established they’re quite hardy but new transplants are somewhat tender, and hard to cover. I like to wait for cloudy days to set them out since they usually don’t get any extra protection while settling in. A kitchen fork makes a good tool to loosen the plants from the flat and the roots from each other. Sometimes I hoe a trench and set the plants in about 5” apart, pulling the dirt back around them as I go. Sometimes I use my long dibble to set the spacing and make small holes, using my fingers or fork to make a larger hole when needed to put the little plant in. Then a good watering if no rain is imminent and they’re done.

That’s it until they’ve grown sturdy and the weather has warmed up. Then they get mulched with sawdust or planer shavings or dried grass clippings. I have used hay but it’s pretty fussy getting it in there without damaging the onion tops. Earlier when the weather is still cold the bare ground helps keep the plants warm and protected from frosts. Later the mulch keeps the soil cool and moist, as well as discouraging weeds.

FRESH Green onions can be pulled anytime throughout the growing season, for the greens or the bulbs or both, chopped into salads or offered for direct munching, or cut up (or not) for the cookpot. Any of the onions in my garden are fair game for this. Early in the season it’s whoever gets large enough first, later it’s the smallest and tenderest fry (for fresh eating) which aren’t going to make a storage bulb anyway. One can grow bunching onions just for this purpose, and I do sometimes, the kind that multiply and don’t make large bulbs. But they seem to get out of hand with the multiplying for me (we just don’t need that many green onions) and it's mostly easier to simply pull appropriate green onions out of my regular crops. Through the summer I pull any “thicknecks” when they’ve sized up enough to be useful since they aren’t going to cure and store as well as bulbs with thinner necks. And any that are growing a seed head (break that off) since they also aren't going to store well.

That’s about it until harvest time. My onions are wonderfully independent. This is my main storage crop. They are usually ready for harvest in September and keep until we run out, often in June or early July, providing good eating along the way. Since most of my cooked meals start with “saute onions and garlic ...” I like to have a bushel or more put up in the fall. It’s an unhappy and thankfully rare year that I have a such a poor crop that we have to buy onions.

onions planted close for setsONION SETS -- Onion sets are readily available in the spring in our area -- paper bags of usually yellow sets of variable quality and unknown parentage and source, but probably all the same. If you sort through and toss half, the rest will make a pretty good crop of reasonable storage onions. You can often get better quality ones from a good seed company if you remember to order them early enough. They’re easy to plant, just push them in where you want them to grow, root side down. But I don’t like to be so limited, I want to know where my plants come from, who they are, and I want diversity. Plus I like to do my own. So, in addition to all the other onion methods I use, I like to grow my own sets. It’s not hard if you plant them at the right time for the weather conditions that year. The weather is a pretty big variable but if all goes well you can have some really nice and easy to plant sets, then other years not so. So I still depend on my seed crop, but sets are easier.

Planting for onion sets is pretty much the same as planting seed for fall onions, but plant them later, in early to mid June, thicker and in wide bands instead of a single row. Best to thin them to maybe a half inch apart. They want some room to grow but keeping them close keeps the bulbs small for nice sized sets. Too close and they’ll not be large enough. Little thinnings are tossed aside but larger ones are used for green onions for salads. Often plants on the edges will get too large for sets but they'll be just fine for use in the kitchen where you might use shallots.

Manage them like regular onions. When the tops start drying down, pull and cure, sorting through and tossing the very smallest specimens. A wide variety of sizes will grow onions the next year but as they get larger they are more apt to send up a seed stalk, and the smallest will have a harder time getting going and making a good sized bulb, plus they don’t keep as well. I go for about a half inch for sets; larger ones we eat. I store them in a small mesh bag in the pantry. In the spring plant them as you would any purchased sets.

I also save the smallest onions from my regular storage crop to plant as “sets” the next spring, even if they’re an inch or more across. These will grow fast and likely set a seed head early but nip this off and they’ll go on to make a good sized onion for summer cooking, or an early green onion for salads..

HARVESTING - STORAGE -- Bulbs to be stored for months for off-season use need to be well cured and treated well. When the tops have yellowed and started to dry I pull the plants. If you wait too long, when the leaves are well along in drying, you’ll have to lift them with a trowel since the tops will pull off when you pull. And if you wait too, too long and the tops are all dried they’re hard to see. Better to get them at the right time, when the green is mostly gone but before they’re dead and drying on their own.

onions curingI harvest on a sunny day when the soil isn’t too wet. Pull the onions and lay them out along the plot in the sun for initial drying and for sorting. Then move them out to a convenient spot in the shade for curing. My favorite is on the plywood floor of our woodshed (in summer it's also a storage shed so space is limited). Most years late summer/early fall is nice enough weather that this works fine. I might also spread the onions out on the lawn somewhere dry and out of the way, taking them under cover at night (when damp settles in or frost threatens), spreading them out again when it’s nice. Basically you want an airy, dry spot out of hot sun for several or more weeks.

Early on when the tops are still a bulky presence a wheelbarrow works well for moving onions around. Later when the tops are drying up (not so much mass) then baskets are nice. Any garden dirt that came along with the bulbs falls off naturally and easily in the handling. Of course, you want to handle your bulbs with reasonable care if you want them to store well.

stored onionsAfter some time of this in and out the tops are all dried and mostly crumpled off, the roots are dried and easy to break or snip off, the skins are nice and crinkly dry. Sometimes I just rub off whatever tops are left and whatever roots want to go and not worry about the rest. Often I sit down with shears and snip off the dried tops and roots, gently rubbing off excess skins and setting them happily in wooden crates or half-bushel baskets. It’s a pleasant task and one I enjoy. Any thicknecks or bulbs not cured yet are put in a separate basket or bucket to be eaten first. Though those thicknecks will last quite awhile, stored in a bucket in the rootcellar. So if you have a year of many thicknecks (some years are like that) don't fret too much. Save your best keepers for later and enjoy the thicknecks earlier.

In those, thankfully uncommon, rainy, rainy harvest years when there just aren’t enough sunny days I spread the onions (along with everything else) in the house in whatever space of floor that can be found, on an old sheet or blanket, to dry down when they will.

POTATO ONIONS -- I love these small guys. They are so easy and they always come through; sometimes smaller, sometimes larger, usually a good crop, occasionally not, but always something. I’ve been growing and replanting them for probably thirty years, through growing seasons too hot, too cold, too dry, too wet (and occasionally just right!). They survive. The flavor is good and though on the small size compared to my regular onion crop, they get particular appreciation since they are ready to eat at just the right time when the last of the stored seed onions are being doled out, eeking through until the potato onions are large enough, usually in July.

Being multiplier onions, they propagate vegetatively underground instead of producing seed. Plant one little onion and you might get one larger (2 - 3”) bulb or a clump of 2-8 smaller bulbs. One year I noted that the smaller sets produced more single large bulbs and the larger single sets (or bulbs) more multiples. Another year there was no such pattern, with variety across the board. Apparently they don’t believe in limiting themselves.

The potato onions are one of the first to be planted out in early spring when I start working in the garden, usually the first of May (though this unusual year it was the first of April! A rarity as we usually still have snow then). I sort through the stored bulbs, throwing out the smallest, dried out, growing or otherwise not healthy looking specimens. Mostly I choose the medium sized, 1/2” to 1” bulbs to plant, having probably eaten the largest ones already. I mark the spots with my long planting dibble (5” spacing) and push the overwintered bulbs in just as one does onion sets, though the larger bulbs will need a little help with trowel or fingers to make a larger hole. You don’t want to hurt them pushing them into the ground. Several feet of bed is plenty for us. Five feet (by four feet wide) spot will produce over a hundred single bulbs and clumps.

At some point I mulch the onions with sawdust, shavings or grass clippings. They are smallish plants and tend to grow out as much as up so smaller mulching material works well. When to mulch depends on the weather, often not until the frosts are over as the warmth from the bare ground helps keep the plants warm, though potato onions are very hardy. If spring is unusually dry, I mulch early.

When the winter stored onions are gone I start eyeing the potato onions. Suddenly a two inch onion is large and makes do in a meal that a three or four incher regular onion would have done earlier. When they’ve size up (and some years before if I’ve run out of stored onions) I harvest mostly the larger, single bulbs for cooking as I need them.

By the end of July the potato onions are mature and leaves have yellowed and are drying down. I pull the bulbs and clumps and let them dry and cure in sun if it’s not too hot or shade if it is (I consider upper 70’s hot). If it’s a rainy spell I spread them out inside or under cover. It’s a small crop and easy to manage. We continue to eat the largest bulbs and when the cucumbers are ready sometimes the smaller bulbs end up in the pickles. Once cured and nicely dry whatever bulbs are left get stored in a mesh bag hung in the cool dry pantry over winter to be planted out next spring. They keep well. I've heard from gardeners who plant their potato onions in the fall and they overwinter well. I haven't tried that yet, but maybe I will this year.

onion seed heads bloomingGROWING and SAVING ONION SEED -- Onion seed is fairly easy to grow if you’ve grown onions from open pollinated seed. Onions grown from hybrid seed generally won’t come true to the parent or may not set seed at all (doesn’t mean you couldn’t try however). All seed producing onions will cross so you’ll want to plant only one variety at a time for seed unless you purposely want them to cross. In the fall when you harvest your onions pick out 9 or more of what you consider to be the best bulbs for your purpose. Replant them just below soil level about 12 inches apart. Mulch them and let them settle in for the winter. In the spring they will grow and send up seed stalks topped by beautiful allium flower balls, which in good years will result in a nice harvest of seed. When most of the little individual seed husks start to dry and you notice them opening up in preparation to dropping their seed, cut the seed ball into a shallow container or paper bag and bring them inside or in a dry protected area to finish drying. Mine are often still rather green so need some time to finish maturing and drying. Even if the weather is nice and dry outside you’ll want to harvest the heads before all of the seed husks are ready to prevent the plant self seeding all over the ground on it’s own which is what it wants to do. I put them in a paper bag or in a open container of some kind to finish drying.

When the seed heads are well dried and rattly and the seed is falling out rub the heads between your hands (leather gloves sometimes does better than bare hands) to finish separating the seed. Gently winnow off whatever trash you can with a low fan or wind. Since it’s just for your own use it doesn’t matter if it isn’t real clean and you risk losing seed if you get over enthusiastic with your winnowing. You can also screen them seed with various sizes of screen to separate out the smallest and largest trash. As with all seed, store in a cool, dry, dark area for planting next spring, and for several years after if you have enough seed. That's the nice thing about growing your own seed. If all goes well, you'll end up with handfuls of seed instead of just a small packet.

OTHER ALLIUMS -- In addition to seed onions and potato onions there are leeks and bunching onions and shallots and garlic. And if all else fails (which it never has nor do I expect it will) there are always chives. Not much can stop a chive. I stopped growing them in the garden decades ago and they are happily growing wild all over instead -- early, late, in-between, and in all kinds of soil. If there is anything green growing outside, there are chives to be had. And one can always head to the woods to harvest some highly flavored wild leeks. Meals need never be too mild or too boring once you become friends with the Alliums.

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Copyright by Susan Robishaw

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