I think Brussels sprouts are one of the most underrated brassicas, because of their incredible flexibility, their winter hardiness and their health giving properties.
They have a unique property that makes them so flexible, they don't easily go to seed in spring, when planted late in the year and over-wintered. While most varieties of the flowering brassicas, calabrese, broccoli and cauliflower, kales and cabbages all naturally start to flower in spring when sown in autumn and grown over winter. But Brussels, for reasons I don't understand, rarely do, or at least Fillbasket doesn't which is the one I grow (I'm testing more this year). This makes them an ideal leaf crop in the Hungry Gap, from early May through to June.
<aside> 💡 When reading this guide please forget everything you know about Brussels from your supermarket experience, or most gardening books and seed suppliers! They are so much better than they would have you believe!
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I use a rating system to help me decide what to grow and it considers lots of factors, but the main ones are: how tasty it is, how healthy it is to eat, how expensive it is to buy, how big its harvest is, when its harvest period is and whether I can buy it organically and if not how much pesticide commercial growers use.
Brussels are not quite as good as Kalettes, but they score high on almost every category and they do well overall, when everything's considered:
If you are growing them just for leaves in spring, then I’d only grow 1 plant per person. Grown for the sprouts it depends a lot on how much you like them. Sown in March in ideal conditions a single plant will probably provide one person with sprouts for a month and you can harvest them for about 3 months on average, so 3 plants per person, which is about 0.7m2/person.
https://airtable.com/shrk89GOTL5dpaE0a
To get the best from Brussels you need to sow two and maybe even three successions. You can think of these as: