Companion Planting: Brussels Sprouts
Brassica oleracea
Spacing: 1 per square foot. Mature height: 2-3 ft.
Plant these nearby
- Onion: Onion scent is reputed to confuse cabbage moths that target brassicas. The research behind this is real but garlic-specific (field trials intercropping garlic with cabbage reduced diamondback moth damage) — onion hasn't been tested the same way, so treat the onion version as a reasonable extrapolation, not a directly measured result.
Keep these apart
- Tomato: Widely repeated that brassicas and tomatoes compete heavily and can stunt each other, but no extension or research source was found testing this specific claim — treat it as garden tradition, not measured evidence.
Common pairings, answered directly
- Can I plant brussels sprouts next to onion?
- Yes. Onion scent is reputed to confuse cabbage moths that target brassicas. The research behind this is real but garlic-specific (field trials intercropping garlic with cabbage reduced diamondback moth damage) — onion hasn't been tested the same way, so treat the onion version as a reasonable extrapolation, not a directly measured result.
- Can I plant brussels sprouts next to tomato?
- Better not to. Widely repeated that brassicas and tomatoes compete heavily and can stunt each other, but no extension or research source was found testing this specific claim — treat it as garden tradition, not measured evidence.
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Companion planting for Brussels Sprouts: which plants to grow next to it, which to keep apart, and the reason behind each pairing.
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