There has been a head of garlic in the fruit bowl since August. You walk past it most days, think you really should get it in the ground, and it is still sitting there.
So the question is fair enough. Can you plant supermarket garlic in Canada and get anything worth eating out of it?
Can you plant supermarket garlic in Canada?
Yes, you can plant supermarket garlic, and it will usually grow something green. What it rarely does is form a full head. Most grocery garlic is softneck grown in a warm climate and treated so it will not sprout on the shelf, so here it tends to give one small round bulb.
In practice that looks like a thin shoot in April and a single lump in July, about the size of the clove you started with. Nine months of bed space for that.
I am Darrell, and I have been growing food around Vancouver for over twenty five years. I have planted grocery garlic myself, more than once, mostly out of curiosity. It is not a disaster. Plant supermarket garlic and you spend a season finding out something you could have known in October.
Why the head in your fruit bowl behaves that way
Three things work against any plan to plant supermarket garlic, and they stack.
The first reason to think twice before you plant supermarket garlic is the type. Supermarkets buy for shelf life and for shipping, which means softneck garlic almost every time. Softneck stores for the better part of a year and it does not have a stiff stalk to fight the packing line. It also comes from places with mild winters, so the plant has no reason to expect what your January is going to do to it.
The second is the treatment, and it is the part people forget when they plant supermarket garlic. Commercial garlic destined for eating is often handled so it will not sprout in the bag. That is a sensible thing to do for a food crop and a hopeless thing to do to a seed crop. You are planting something that has been asked, chemically or by careful cold storage, to sit still.
The third is what it might be carrying, and it is the strongest argument against any plan to plant supermarket garlic.
What is the risk of planting grocery garlic in your soil?
The one that matters is white rot, caused by the fungus Stromatinia cepivora. It produces tiny resting bodies called sclerotia that survive in soil for decades without a host, and it affects garlic, onions, leeks and shallots. Once it is in a bed, you are not digging it back out.
That is not a scare story I invented to sell seed garlic. It is well documented in agricultural extension work, including the University of California IPM programme, and it is the reason commercial growers are careful about where their planting stock comes from. The signs are yellowing leaves, a plant that pulls out too easily, and white fluffy growth with small black specks at the base of the bulb.
The odds of any single grocery head carrying it are not high. The problem is that the downside is permanent and the upside was a bulb the size of a marble. That is the whole reason I stopped telling people to plant supermarket garlic in a bed they care about.
When it is reasonable to plant supermarket garlic
There are cases where I would say go ahead and plant supermarket garlic.
If you bought the garlic from a farmers market or a local grower, you are not really buying supermarket garlic at all. That head was grown in a climate close to yours, it has probably not been treated, and it may well be hardneck. Ask the grower which type it is. Most of them enjoy the question.
If the head in your bowl has already sprouted green shoots on its own, the sprout inhibitor either was not used or has worn off. It will grow. Put it in a container rather than your main bed so that whatever it might be carrying stays contained, and treat it as an experiment.
And if you simply want green garlic, the young leaves you snip like chives, grocery cloves are fine. Plant them close together in a pot, cut the greens, and never mind about heads at all. If you go that way, our notes on growing garlic in containers cover the pot depth and the watering.
What seed garlic actually is
Seed garlic is the same plant. What separates it from the head you would plant supermarket garlic from is what it was grown for and how it was handled after harvest.
It is grown for planting rather than eating, which means the grower selects for bulb size and health rather than for how long it will last in a shipping container. It has not been treated to suppress sprouting. It comes from stock that is inspected for disease. And in this country it is almost always hardneck, because hardneck is what stands up to a Canadian winter and splits into a full head after months of cold ground.
If you want the longer version of that comparison, I have written up the difference between hardneck and softneck garlic and which one suits which part of the country.
The three hardneck varieties we put together for Canadian winters arrive as nine seed bulbs, which covers a small bed or a long planter and lets you compare three flavours from one October afternoon.
How to tell good planting stock in your hand
This part you can do yourself, whether the garlic came from us, from a market stall or from a friend down the road.
Pick the head up. It should feel heavy for its size and firm all the way round, with the papery skin mostly intact. Press gently at the shoulders. If anything gives, that head has started to break down in the middle and it will not do much except take up space in your bed. Turn it over and look at the base plate where the roots come from. You want it dry and hard, not spongy or hollow.
Nobody ran that check on the head you were about to plant supermarket garlic from, and nobody can run it for you through a screen, which is why we order in small lots and open every box by hand.
The other half of the job is what you do on planting day, and the biggest lever there is which cloves you choose to put in the ground.
Getting the bed ready
Whether you sow proper seed stock or plant supermarket garlic, garlic has fine roots and does not compete well, so clear the weeds out properly first. It wants ground that drains, which on the coast usually means adding organic matter or planting into a raised bed. If your soil sits wet all winter, preparing a raised bed before the rain sets in is time better spent than anything else you could do this month.
What next July looks like if you get this right
You are lifting heads with a fork in mid July, brushing soil off, and hanging them somewhere airy in the garage to dry. Before that, in June, you are cutting curled scapes off the hardnecks and cooking them, which is a harvest most people have never eaten.
Our seed garlic comes in small lots and once a variety is spoken for there is no reordering it midway through the season.
Have a look at the seed garlic we chose for this fall and see which varieties suit your cooking.
If you would rather watch than read, Darrell covers what a full season of garlic looks like from planting to harvest in a short video on our channel.
What it costs to plant supermarket garlic, and what we do instead
The bill for a decision to plant supermarket garlic arrives late, which is why it feels free. You give up a bed from October to July, you water it, weed it and wait out a winter, and then you lift a row of single round bulbs and buy garlic at the shop anyway. The head in the fruit bowl looked like it cost nothing.
There is a second cost that never shows on a receipt. White rot sits in soil for decades once it arrives. Nobody can promise you a grocery head is carrying it, and nobody can promise you it is not, and that uncertainty is the part that keeps people awake at eleven at night with a forum open.
Garlic is also a crop people give away. It goes into jars at Christmas, over the fence in July, into a paper bag for whoever helped you move the compost. A bed that fails is not just lost food, it is the small thing you were quietly looking forward to handing somebody.
So we handle the part we can. Seed garlic comes in small lots, the cartons are opened here rather than at your door, and every bulb is felt at the neck and weighed in the hand before it is packed. Darrell has more than 25 years of hands on gardening and landscaping behind him, and he planted grocery cloves himself before he stopped recommending it.
Do it properly and next July you are hanging full heads in the garage. Choose to plant supermarket garlic in ground you care about and you may be buying a season of waiting.
Frequently asked questions
Will supermarket garlic grow at all if I plant it?
Usually it will produce leaves and often a small bulb, particularly if the head has already begun sprouting on its own. What it rarely does in a Canadian garden is split into a proper multi clove head, because the variety was chosen for a mild climate and the stock was handled to keep it dormant on the shelf.
Is organic supermarket garlic better for planting?
Somewhat, because organic garlic has not been treated with a synthetic sprout inhibitor, so it is more likely to grow. It is still usually softneck from a warm growing region, and it still carries the same soil disease risk as any eating garlic. Better odds, same underlying problem.
Can I plant garlic in spring instead?
You can, but hardneck garlic needs a long cold stretch underground to divide into cloves. Plant in spring and you have skipped the part that does the work, so most people pull up a single round bulb in summer. If you have missed the fall window, plant a few in pots for green garlic and put the bed in properly next October.
Where do I buy seed garlic in Canada?
Garden centres, seed houses and local growers all sell it in late summer and early autumn, usually in small quantities because it is bulky to ship. Buy from somewhere that will tell you the variety name and whether it is hardneck or softneck. If they cannot answer that, they do not know their stock.
Come and see it in person
If you are in Kitsilano or nearby on the Vancouver Westside, come and pick a few heads up. Feeling the weight of a good seed bulb next to a supermarket one settles the argument faster than anything I can write.
DH Garden Centre
3742 West 10th Avenue, Vancouver, BC V6R 2G4
Open daily, 11:00 to 18:30
604-929-7335
Keep reading
Have a plant question? Bring it to the counter.
DH Garden Centre is at 3742 West 10th Avenue in Kitsilano, Vancouver, open 11:00 to 6:30 every day. Bring the plant, or a photo of the spot you want to fill, and we will look at it with you. If you buy a pot here we repot the plant at the counter, soil included up to 5 litres.
