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 four tries to finally grow Brussels sprouts worth eating, and now I will share with you how I grow them 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.
If you’re more of a visual learner, check out the video below for a glimpse of my Zone 3 garden and a bit about how I grow (almost) bug-free Brussels sprouts:
Are Brussels 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 Brussels sprouts need to be both started from seed and put outside much sooner than that.
The Brussels sprout seedlings below were started ten weeks before our last frost date–around the first week of March.
Since Brussels 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 is the key to my Brussels sprout growing success.
The Brussels sprouts in these photos 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, keep them in the ground until the temperature drops to around -10°C/14°F or lower. When writing this post, it was the beginning of October and my plants (except the one I pulled in the video) were still in the ground.
Can you Grow Brussels Sprouts in Raised Beds?
Yes! In fact, if you watch the video, my Brussels sprouts were living quite happily in raised beds. I gave them around 18 inches of room that year, but I gave them closer to 24 inches the following year. If you’re a square-foot gardener, that means that you’ll plant each Brussels sprout seedling in the middle of four 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 four of my free plans below:
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What insects eat Brussels 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 it’s 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, which was not nearly enough. Now I make them at least 4 feet tall, so I can keep them on through most of the bad bug pressure.
Unfortunately, the bug fabric won’t keep out the slugs. For that, I set out pie plates with beer and copper tape. If that doesn’t work, I’ll try slug bait or a spray (I use ones like Sluggo that are safe for pets and wildlife).
Finally, if aphids are the bug plaguing your vegetables, you can buy a colony of ladybugs from your local garden centre. Lady bugs eat aphids, so they’re a great natural pest control.
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!
How to Harvest Brussels Sprouts
If you’ve never grown Brussels sprouts before and have only seen them in the grocery store, you might not know that they grow along tall stems with big leaves stretching out. To harvest Brussels sprouts, pull out the plant and cut off all the branches. Then, rip off the individual heads and clean them.
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 oil with a little salt, pepper, parmesan cheese, and garlic powder.
And that’s how you grow Brussels sprouts from seed! All it really takes is knowing the right timing and protecting your sprouts from bugs from day one.
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