Unless you grow plants exclusively in containers, it is important to change where you sow your crops each year. Rotating plants protects them and improves the nutrition that they have available to them:
- Disease organisms and insects that are harmful to a particular plant may build up in the soil over time, leading to crop failure should the same plant be sown in that same area.
- Some plants may consume more of one nutrient than others, leading to soil depletion and crop failure should they remain in the same area year after year.
- Some plants, such as legumes, benefit the soil. Moving them around helps to improve the soil throughout the garden rather than in just one spot.
How it works
The easiest way to rotate your vegetables is to put them in groups (keeping the principles of companion gardening in mind), and then rotate the groups. The most common grouping scheme employs the following four groups, although you may choose to use more complicated groupings if you have a large garden or a large variety of plants:
Legumes, which restore nitrogen in the soil, such as peas and beans, as well as potatoes. Potatoes are root vegetables, but they can suffer from the same blights as tomatoes and other fruits, so we do not want them to follow each other.
Leafy plants that quickly use up nitrogen, such as cabbage, greens, spinach, herbs, broccoli, and corn
- Fruits, such as tomatoes, peppers, melons, eggplant, and squash.
Light feeding roots, such as carrots, onions, garlic, and rutabaga.
So here is how we would rotate our vegetables:
- Leafy plants go where the legumes were the year before, because they need a lot of nitrogen.
- Fruits follow the leafy plants because they need the phosphorus that the leafy plants provide, and too much nitrogen stifles the growth of their fruit.
- Roots follow the fruits because they need the potassium that the fruits provide, but less nitrogen. They don’t like rich soil.
- Legumes follow the roots to put nitrogen back in the soil. They also like that the root crops loosen the soil.
So, if you split your garden into four sections, you could plant each section with one of the above-numbered groups, using the following four year schedule:
- Year 1: 1234
- Year 2: 2341
- Year 3: 3412
- Year 4: 4123
If you use raised beds or planters, and change the soil yearly or so, you may not need to rotate your plants. Some plants, such as lettuce, have few pests, so they can remain in the same place for a few years if you have a smaller garden.