Growing fall onions usually comes down to one question – “What onions can be grown this fall?” Sweet onions are the safest bet, we’ll show you why!
Rich, slow-cooked caramelized onions are a simple treat. Charcoal grill roasting adds a smoky element to the sweet, complex flavors with only 3 ingredients.
Growing fall onions is sometimes confusing – should you choose the long day or day-neutral ones? When should you plant? Does the color of the onion matter? How to avoid growing non-bulbing onions again this year?
Most questions come down to, “What onions can be grown this fall?”
The short answer is the sweet onions will do best in almost all locations, but there is more to the answer!
Most gardeners can successfully grow the sweet Candy onions for cooking.
There are three conditions fall-grown onions need – day-length, time to mature and temperature.
Candy is a day-neutral onion, meaning it forms a bulb with 12 – 14 hours of daylight. The map above shows approximately where the Candy onion will grow. The southern limits are short day length and the northern are too cold too early for a sweet onion in the fall.
Our grower has had excellent results in almost all regions of the US. The exceptions are south Florida, south Texas and the extreme northern states bordering Canada. Even parts of Maine have been able to grow good sweet onions in the fall!
Our sweet onion needs about 90 – 100 days to mature into good sized bulbs ready for harvesting. This is just over three months, so check your freeze dates to see if you’ve got enough time.
Light frosts aren’t a concern with onions as they continue growing until the first hard freeze.
If you aren’t sure of your medium frost dates, take a few minutes to read our article on understanding your frost dates. How to Plan for Fall and Winter Gardening will get you up to speed!
You are looking for the Fall 24°F date (the orange circle) from your local historical weather data.
This brings us to temperature…
Onions are remarkably tolerant of frosts and even moderate freezing weather. They go dormant and then resume growth when favorable conditions return. Winter temperatures down to the early 20’s won’t damage onions if mulched and protected.
An old grower once told me some of the sweetest onions he ever grew were over-wintered ones.
He planted bulbs in the early fall, let them grow and mulched heavily 6 – 8 inches deep just before the first frosts. They went dormant in the winter and when spring came he removed the mulch. The onions resumed growing as spring warmed up. He had the earliest harvest of incredibly sweet, delicious onions.
He would never sell these, as they were too special! He shared them with family and close friends.
Knowing these 3 factors, you will be more successful growing your onions this fall.
As the famous radio host Paul Harvey used to say, “Now you know the rest of the story!”
Slow cooked caramelized onions are great, but what if you took that further?
Like, a lot further. Say, six hours full of slow cooked, caramelized goodness.
You would wind up with what Chef Michael Solomonov makes at Zahav, his Israeli-inspired restaurant in Philadelphia.
1â„2 cup olive oil6 lbs yellow or sweet onions (about 12 large), choppedKosher salt or sea salt to tastePlace the onions in a heavy heat-retaining pot. I’ve used cast iron for over 20 years and haven’t found anything better for this type of cooking!Pour the olive oil over the top of the chopped onions, then sprinkle the sea salt and stir well.
Chop the onions into smaller pieces. I love using sweet onions as they add a layer to the flavors, but any mild onion will work well.
Of course, growing your own onions will give you the absolute best flavors, but a close second is your local Farmer’s Market. Look for the large, fat, sweet onions for this recipe. Yellow or sweet onions give excellent flavors, but red or purple onions will do just as well with a different color and flavor.
Early fall is a great time for planting onions to over-winter and finish growing next spring – giving you an extra dose of rich flavor and sweetness.
Add the chopped onions to the pot, add the olive oil and salt, then give a good stir to coat the onions.
Put on the covered grill or oven set to 250°F.
The pot of onions has just been put on the Kamado, where I was pre-roasting a chicken for a clay pot dish with onions and Poblano chiles.
Note how full the pot is – within a half inch or so of the top. As we progress, you’ll see how much this drops!
Smoking means cooking! The smoke always means a delicious meal is on the way.
The beauty of slow cooking outside is the freedom it gives you. There is no need to stand around the grill, you can do projects, read or take a nap and check the progress every so often. I try not to lift the lid more than twice an hour, to not lose heat and smoke.
After a couple of hours the onions begin to caramelize. Give them a stir at this point, then about once an hour.
See how much the level has dropped?
The lid is left off so the moisture evaporates and the smoke can infuse the onions.
No, these aren’t burned – they are finished!
What started out as a full pot has cooked down to just a couple of cups. All of those flavors have condensed and intensified, mellowing with the gentle heat and smoke from the grill.
Remove from the pan, let cool and store in the refrigerator for up to a month. They won’t last past a few days, but they will keep up to a month!
Now that you’ve got some smoky caramelized onions, what do you do with them?
Almost anything you want!
They are delicious as appetizers straight on crackers, spread on the bun of a fresh-grilled hamburger or as a remoulade on a steak. Mix half-and-half with our 30 Second Mayonnaise for a sandwich spread that will amaze! Chef Michael serves them mixed with salads, slathered on roast chicken, spread on toast with ricotta cheese, or swirled in sauteed chopped collard greens as a rich side dish.
I like them straight, spread on crackers for that full blast hit of flavors and smokiness. Spread on burgers is sublime as well.
Give this a try and let me know how you like them and what you use them on!
Fall Onions Made Easy
Growing fall onions usually comes down to one question – “What onions can be grown this fall?” Sweet onions are the safest bet, we’ll show you why!
Six Hour Caramelized Onions
Rich, slow-cooked caramelized onions are a simple treat. Charcoal grill roasting adds a smoky element to the sweet, complex flavors with only 3 ingredients.