Broccoli + Cabbage

Broccoli and cabbage are both brassicas, which makes them poor candidates for adjacent planting. Shared family membership means shared vulnerabilities: cabbage loopers, imported cabbageworm, aphids, and clubroot fungus move freely between them when planted close together. Rather than diluting pest pressure, proximity concentrates it.

Separate these crops by at least one bed width, and rotate both out of brassica ground annually. Most university extension programs recommend a three-year rotation minimum for clubroot management. Timing does not resolve the problem; even sequential plantings in the same bed carry over soil-borne disease inoculum.

For gardeners with limited space, this pairing forces a real trade-off. If only one bed is available, choose the crop better suited to the current season rather than trying to fit both. In practice, treating broccoli and cabbage as competitors for the same bed slot, rather than companions, produces more consistent results.