Crop Rotation and Why It Is Necessary

Crop rotation is the simple practice of changing where you plant each type of vegetable every year. This does not mean digging a completely new garden each year, don't worry. It simply means don't plant tomatoes in the same spot yearly. Or any other type of vegetable in the same spot each year.

We could plant vegetables in the same location each year; it's an easy thing to do. But, for the healthiest, most productive garden, it is essential to break the cycle and switch up the locations of your vegetable crops.

Reasons For Crop Rotation

Pests & Disease

Unfortunately, pests depend on us to plant crops in the exact locations. Many pests overwinter in the soil, hoping you'll plant their favorite vegetable on top of them the following year.

When we plant beans in the same spot year to year, we're basically providing a free all-you-can-eat buffet for the bean beetle larvae right on top of their home. We try not to let it be that easy for them! By planting on the other side of the garden, the beetles have to work harder if they want to find the beans. Ideally, it is far enough away that most can't find them at all.

This is the same for plant diseases. The pathogens sit in the soil, waiting for their favorite host to appear, then attack. It's very nice for them when you plant in the same spot as the previous year.

Soil Health

Another reason crop rotation is important is that some vegetables take more from the soil than others. Leafy vegetables take up lots of nitrogen. A nitrogen-deficient environment results if you plant them in the same spot each year. Eventually, the lettuce will struggle to grow. On the other hand, peas and beans add lots of nitrogen to the soil, making them the ideal vegetable to plant the year following a lettuce crop.

Plant Rotation Guidelines:

The key to successful crop rotation practices is to avoid planting crops from the same family in the same location one year to the next. For example, you may move broccoli to a new location to avoid pests, but if you put cabbage there instead, it will have the same issues. This is because plants in the same family suffer from the same pests and diseases.

And the same issue applies to soil nutrients and health. Planting broccoli in the same spot each year will take all the nitrogen until the soil in that area becomes deficient. However, planting a legume nitrogen-fixer in the spot will fill the soil with adequate nitrogen for the following years' brassica planting.

Plant Family Groupings:

Legumes: Green peas, green and yellow beans, soybeans, peanuts. Legumes are nitrogen-fixers; they add nitrogen back into the soil.

Brassicas: Broccoli, cabbage, cauliflower, brussels sprouts, kale, radishes, collard greens, mustard greens, Chinese cabbage, and turnips. All of these vegetables share pest issues. They all also require nitrogen-rich soil.

Alliums: Onions, garlic, leeks, shallots.

Nightshades: Tomatoes, peppers, eggplant, potatoes. These are all heavy feeders which require rich soil. They're also all subject to the same pests and diseases. It is imperative not to plant tomatoes after potatoes.

Cucurbits: Cucumbers, zucchini, summer squash, pumpkins, melons, and winter squash. All of these are heavy feeders which need nutrient-rich soil.

Umbellifers: Carrots, dill, fennel, parsley, parsnips

Okra, corn, and sweet potatoes are all the single members of their families. Perennial crops, of course, should never be moved.

Crop rotation creates a healthier, balanced soil free from diseases and significantly fewer pests.