Plant family

Collard greens belong to the brassica family, also called the cole crops or cabbage family. Close relatives that share the same pests and diseases include cabbage, broccoli, cauliflower, kale, Brussels sprouts, kohlrabi, turnips, radishes, and mustard greens.

Why rotate collard greens

When brassicas grow in the same ground year after year, soilborne problems like clubroot and black rot accumulate and can persist in the soil for many seasons. Pests such as cabbage root maggot, flea beetles, and overwintering cabbage worms also settle into repeatedly planted beds. On top of that, collards draw heavily on nitrogen, so replanting the same family in one spot steadily depletes the soil and leaves later crops underfed.

What to plant after

Collards do well following legumes such as beans, peas, or clover, because these crops fix nitrogen in the soil and leave behind the extra nitrogen that this leafy, heavy-feeding crop needs. They also make a good choice after a legume cover crop or after light feeders like onions and garlic that do not host brassica pests.

What to avoid

Avoid planting collards right before or after any other brassica, including cabbage, broccoli, cauliflower, kale, turnips, radishes, and mustard, since they all share the same diseases and pests that carry over in the soil. Planting one brassica after another gives clubroot, black rot, and cabbage root maggots an unbroken food supply and defeats the purpose of rotation.

Example rotation

A simple four-year plan for one bed could go like this: Year 1 plant legumes such as bush beans or peas to build nitrogen, Year 2 plant collards and other brassicas to use that nitrogen, Year 3 plant tomatoes or peppers, and Year 4 plant root crops like carrots, beets, or onions. In Year 5 you return to legumes and repeat, which keeps collards off the same ground for about four years.

Tips

Keep a simple garden map or notebook each season so you always know where the brassicas grew and can wait at least three to four years before bringing them back to the same bed. Grouping all your brassicas together in one bed makes them easy to move as a unit, and sowing a legume or grass cover crop in the off season helps rebuild nitrogen and structure before collards return.

General guidance for US home gardens. Adapt to your own crops, soil, and space; your Cooperative Extension office can help with a plan for your area. Page updated Aug 4, 2026.