Brussel sprouts can be tricky to grow in a cold climate with a short growing season, like zone 3. They take a long time, are prone to bug pressure, and take up a lot of space. However, the taste of an organic, homegrown brussel sprout roasted to perfection makes it worth it!
It’s taken me 4 tries to finally grow brussel sprouts worth eating, and now I’m going to share it with you how I grow it from seed. My advice will work best for those who garden in zones 2, 3, and 4, but the bug pressure advice should work for any gardener in any zone.
So here’s how I grow (almost) bug free brussel sprouts in my zone 3 garden.
Before I get into the details, I know some of you would rather watch a video than read every detail. You can see me and my real life garden in the video below:
Alright, on to the good stuff!
Are Brussel sprouts easy to grow from seed?
Yes, but in a short growing season you’ve got to get the timing right. The bulk of my garden typically gets planted around the May Long weekend in Canada (sometime around May 20th), but brussel sprouts need to be both started from seed and put outside much sooner than that.
These brussel sprout seedlings were started 10 weeks before our last frost date–around the first week of March.
Then, since brussel sprouts love and can handle the cold, I put them out in my raised beds under frost cloth and hoops around the beginning to middle of April. This step was the key to my success this year.
The brussels sprouts thrived in the cooler spring weather and were not stunted in size by staying in a seed starting pack for a longer time. The frost cloth kept them warm enough, but it was okay if there was a killing frost overnight, because brussels sprouts can handle colder temperatures.
It’s key to remember this fact in the fall. When it’s the beginning of September and the first frost comes, don’t worry about covering your brussels sprouts–they’ll be totally fine. In fact, if your brussels sprouts are still on the small side, just keep them in the ground until the temperature drops until around minus 10 celsius or lower. At the time of writing, it’s the beginning of October and my plants (except the one I pulled in the video) are still in the ground.
Can you Grow Brussels Sprouts in Raised Beds?
Yes! In fact, if you watch the video, my brussels sprouts are living quite happily in raised beds. I gave them around 18 inches of room this year, but next year I will give them closer to 24 inches. If you’re a square foot gardener, that means that you’ll plant each brussel sprout seedling in the middle of 4 squares.
P.S. If you need help with the spacing in your square foot garden, I personally love and use the Seeding Square, and you can also get 4 of my free plans below:
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What insects eat Brussel sprouts? (And what do I do about it?)
One of the things that make brussel sprouts so difficult to grow is that so many bugs like to eat them! Flea beetles, slugs, aphids, and more all love to get into them. It’s also frustrating, because of the way brussels sprouts leaves overlap each other, once the bugs get in they can’t really get out, and its very difficult to get rid of them.
Sadly, the best way to “get rid of bugs” from brussels sprouts is to prevent them in the first place. To do that, I keep the frost cloth over the plants as long as possible, as they also keep out most of the bugs. You can replace the cloth with actual bug cloth if you wish once the risk of frost is over.
The only downside of preventing bugs this way, is that you need to make the hoops really tall. Mine were only about 2-3 feet tall, and it was not nearly enough. Next year I will make them 4 feet tall, so I can keep them on through most of the bad bug pressure.
To make your own hoop system for keeping out bugs, read this post for creating one in rows, or this post for a raised bed version.
Unfortunately, the bug fabric won’t keep out the slugs. For that, I’ll be setting out pie plates with beer, and setting out copper tape. If that doesn’t work, I’ll try slug bait or a spray. Use one like Sluggo that’s safe for pets and wildlife.
Finally, if aphids are the bug that’s plaguing your vegetables, you can buy a colony of ladybugs from your local garden centre. Lady bugs naturally eat aphids, so they’re a great natural pest control.
How to Harvest Brussels Sprouts
If you’ve never grown brussels sprouts before and only seen them in the grocery store, you might not know that they grow along very tall stems with big leaves that stretch out. To harvest, pull out the plant and cut off all the branches. Then rip off the individual heads and clean them. That’s it!
If you watch the video up above, you’ll see how easy it is to snap them off.
In the kitchen, wash the brussels sprouts off, cutting off the ends and any sketchy looking bits. Then either eat them that evening or put them in a bag to freeze.
As for eating them, I like to keep it simple and roast them in the oil with a little salt, pepper, parmesan cheese, and garlic powder.
So that’s how you grow brussels sprouts from seed. All is really takes is knowing the right timing and protecting it from bugs from day 1.
I’d love to know in the comments if you have any additional growing tips to share. Please mention what zone you’re in, as it helps other readers. Thanks!
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Kristen is a former farm kid turned urban gardener who owns the popular gardening website, Shifting Roots. She is obsessed with growing flowers and pushing the limits of what can be grown in her zone 3b garden. She also loves to grow tomatoes, but oddly enough, dislikes eating them raw.