How do I do crop rotation on a small plot?

Crop rotation is one of the most repeated pieces of garden advice and one of the least well explained. It does two separate jobs — managing soil-borne pests and diseases, and sequencing what each crop takes from and leaves in the soil — and it does them well at field scale and only partially in a garden where beds are two metres apart.

Step by step

1. Sort your crops into families, not into what you cook them with.Legumes: peas, beans. Brassicas: cabbage, kale, sprouts, broccoli, cauliflower, swede, turnip, radish, rocket. Roots and alliums: carrot, parsnip, beetroot, onion, leek, garlic. Potatoes and tomatoes outdoors. Everything else — courgettes, squash, sweetcorn, salads — is flexible and fills gaps.
2. Move each group on one bed each year.In a four-bed system, legumes to where the brassicas were, brassicas to the roots, roots to the potatoes, potatoes to where the legumes were. After four years the cycle repeats.
3. Understand why the order is what it is.Legumes fix nitrogen; brassicas follow to use it, and want firm limed ground. Roots follow, wanting soil with no fresh manure. Potatoes take the manure and their cultivation breaks the ground up for the legumes.
4. Put the manure on the potato bed only.Manuring one bed a year and letting the rotation carry it round means roots never get the fresh material that makes them fork, and brassicas get firm settled ground rather than fluffy soil.
5. Lime the brassica bed, not the potato bed.Brassicas want a near-neutral pH and it suppresses club root. Potatoes prefer it slightly acid and lime worsens scab. Rotating the lime with the brassicas handles both.
6. On a small plot, prioritise rather than idealise.Three crops matter most: brassicas (club root), onions and leeks (white rot), potatoes (eelworm and scab). Move those every year without fail, and let everything else fit around them.
7. Write it down.A simple sketch of the beds with what was in each, kept year to year, is worth more than any system in your head. Rotation only works if you can remember what was where three years ago.
8. Be realistic about what it cannot do.Rotation does nothing about blight, which arrives on the wind. It will not clear established club root or white rot, which outlive any garden rotation. And on beds a metre apart, isolation is partial at best.
9. Use containers or a new bed to break a cycle.Where a soil problem is established, growing that crop in large pots of fresh compost is the practical route, not more rotation.

Tips

• Green manures fit neatly into rotation gaps — sown after a crop is cleared, they hold nutrients and protect the soil until the next planting.
• Perennials — asparagus, rhubarb, globe artichokes — sit outside the rotation entirely and need their own permanent bed.
• If you have inherited a plot, ask the previous holder what grew where. It saves you three years of guessing.
• Rotation also spreads the workload: each bed has a different rhythm of clearing, manuring and planting.

Common mistakes

• Grouping by what looks similar rather than by family — Swede, turnip, radish and rocket are brassicas despite being root and salad crops. Grouping them with carrots defeats the purpose.
• Expecting rotation to prevent blight — Blight is airborne and arrives wherever the crop is. Rotation is about soil-borne problems only.
• Manuring the root bed — Fresh organic matter makes carrots and parsnips fork. It goes on the potato bed and travels round with the rotation.
• Not keeping a record — Three years on, nobody remembers. A sketched plan each spring takes five minutes and makes the whole system possible.

Alternatives

• Four-bed rotation: The classic. Legumes, brassicas, roots and alliums, potatoes. Clean, easy to remember and well matched to an allotment plot.
• Three-bed rotation: Combines legumes with the flexible crops. Simpler for a garden with three beds, and still moves the three groups that matter most.
• Prioritised rotation: Ignore the formal cycle and simply never grow brassicas, alliums or potatoes in the same place two years running. Honest and effective in a small garden.
• Containers for problem crops: Where club root or white rot is established, growing that family in large pots of fresh compost sidesteps the soil entirely. The only genuinely reliable answer on infected ground.
• No rotation with heavy organic matter: Some no-dig growers rotate loosely or not at all, relying on soil biology and healthy plants. It works for many crops but is a real risk with club root and white rot present.

Questions people ask