Crop Rotation in the Home Garden

Article first published on The How Do Gardener.

We’ve all heard of the expression “Too Much of a Good Thing” and can probably name at least a few times where we may have experienced it ourselves. Too much chocolate cake, too much sun, too much time spent digging in the garden after a long winter. Our bodies have a way of letting us know that we did, in fact, overdo things a bit.

Just as that case of sunburn will remind us to stay out of the sun for a while, the soil that we grow our vegetables in lets us know that it’s time for a change by producing fewer and less healthy crops over time. But, by employing a technique long used by farmers in our own home gardens, we can help keep our soil healthy and producing an abundant harvest for many years.

Crop rotation is the practice of growing different crops, on the same land, in sequential planting cycles ranging from 2 to 8 years. Farmers have used crop rotation for centuries as a means of reducing crop loss due to disease and insects, as well as replacing essential nutrients, used by plants while growing, back into the soil. It was first mentioned in early Roman literature, and George Washington Carver is widely credited with introducing crop rotation to the United States by rotating peanuts, sweet potatoes, and cotton.

Soil borne pathogens, and insects, that attack one member of a plant family frequently will infect or attack other plants in that same family. Planting similar plants in the same location, year after year, tends to make the soil in that location much more prone to the diseases and insects that harm those plants.

Different crops take varying amounts of different nutrients from the soil as they grow and produce fruit or vegetables. If similar plants continue to be planted in the same location year after year, the nutrients in the soil inevitably become unbalanced to the point where even the addition of fertilizers may not entirely correct the deficiency.

There is no hard and fast rule as to which plants should be planted after another when practicing crop rotation, whether in the farmer’s fields or in the home garden. The most effective and easiest crop rotation system involves grouping vegetables into six different groups (see table below), each of these groups having similar insect, disease, and soil nutritional content requirements. Never plant a vegetable from the same group, in the same location, two years in a row. Waiting three years before planting a vegetable from the same group is even better.

For example, if this spring you plant Tomatoes, a Group III plant, in a particular spot in the garden, you could plant Broccoli, a Group II plant, in that same spot this fall, and then Cantaloupe, a Group I plant, in that spot next spring. By sequentially planting warm and cool season crops from different groups, you will maximize your garden’s production while maintaining good crop rotation practices.

Although it takes a little advance planning to implement crop rotation in your home garden, the increased health and production of your vegetables will make you glad you put the effort into doing so. And after you’re done planting, go ahead and reward yourself with a nice piece of chocolate cake, but only one.

Crop Rotation Planting Groups

[ Group I ]
• Cucurbitaceae (Gourd Family)
–    Cucumber
–    Watermelon
–    Cantaloupe
–    Honeydew Melon
–    Summer Squash
–    Winter Squash
–    Pumpkin

[ Group II ]
• Cruciferae (Mustard Family)
–    Cabbage
–    Broccoli
–    Cauliflower
–    Kohlrabi
–    Collard
–    Kale
–    Brussels Sprouts
–    Chinese cabbage
–    Turnip
–    Radish

• Chenopodiaceae (Beets Family)
–    Swiss Chard
–    Spinach

• Compositae (Sunflower Family)
–    Lettuce
–    Globe Artichoke
–    Jerusalem Artichoke

[ Group III ]
• Solanaceae (Nightshade Family)
–    Tomato
–    Pepper
–    Eggplant
–    Potato

• Convolvulaceae (Morning-glory Family)
–    Sweet potato

• Malvaceae (Cotton Family)
–    Okra

[ Group IV ]
• Alliaceae (Allium Family)
–    Onion
–    Garlic
–    Leek
–    Shallot

• Chenopodiaceae (Beets Family)
–    Beets

• Umbelliferae (Parsley Family)
–    Celery
–    Carrot
–    Parsnip
–    Parsley

[ Group V ]
• Gramineae (Grass Family)
–    Sweet corn

[ Group VI ]
• Leguminosae (Pea/Bean Family)
–    Snap Bean
–    Pea
–    Cowpea
–    Black-eyed Pea