Disease builds in the soil
Planting the same crop family in the same soil year after year allows specialized diseases and pests to build up. Tomato blight, fusarium wilt, and root-knot nematodes all accumulate in soil where their host plants grow continuously.
Rotate by family
Rotate so that members of the same plant family do not return to the same bed for 3 to 4 years. The major families: nightshades (tomatoes, peppers, eggplant, potatoes), brassicas (cabbage, broccoli, kale), legumes (beans, peas), cucurbits (squash, cucumbers, melons), and alliums (onions, garlic).
A simple 4-bed rotation: Bed 1 gets nightshades this year, legumes next year, brassicas the year after, then cucurbits. Each family moves one bed forward each season.
Beyond disease prevention
Legumes fix nitrogen in the soil, benefiting the heavy-feeding crop that follows them. Rotation also distributes nutrient demands more evenly and reduces the need for synthetic fertilizers.
- Rotate crop families: 3-4 years before the same family returns
- Major families: nightshades, brassicas, legumes, cucurbits, alliums
- Follow heavy feeders with legumes (nitrogen fixers)
- Simple 4-bed rotation: each family moves one bed per season
- UGA Extension — Crop rotation guidance for home gardens.