Growing the same crops in the same soil year after year does not only make it an easy target for pests and disease but also results in depleted soil nutrients and decreased crop productivity over time. To avoid this, you can easily adopt a crop rotation plan in your vegetable garden, big or small.
The basic principle of crop rotation is to not grow the same crop in the same soil for a period of three to four years. Different crops take up different levels of nutrients from the soil, inevitably causing an imbalance in soil nutrient levels, depleting one nutrient but leaving a lot of another. Also, Plants from the same family, are vulnerable to the same pests or diseases, and should therefore not be planted in the same pace year after year.
Why crop rotate?
To improve soil fertility over an extended period of time and maintain healthy soil-microbial activity.
To prevent the build-up of soil-borne pests and diseases specific to a crop, which in turn lessens the use of chemical pesticides.
To suppress and reduce weeds. By planting a variety of crops with a variety of characteristics will prevent a weed species to become adapted to the system.
How does it work?
The vegetables we grow can be grouped into four main groups. Each main group includes plants that are similar in characteristics and nutritional needs.
Light feeders - Leafy greens that need a good amount of nitrogen to produce a harvest, e.g. lettuce, kale, spinach, chard, cabbage, cauliflower, as well as herbs.
Heavy feeders - Fruit-producing crops that need a good dose of phosphorous and small amounts of nitrogen, e.g. tomatoes, cucumbers, squash, melons and peppers.
Root crops - Potassium-hungry crops e.g. onions, garlic, radishes, carrots, beets and turnips.
Legumes - Nitrogen-fixing crops e.g. french beans, peas, runner beans, broad beans, and may also include alfalfa, clover and fenugreek.
To find out more about the important roles that nitrogen, phosphorous and potassium have in your garden, the article below will help you dig a little deeper.
A growing area is divided into four plots and each plant group is allocated its own plot. After the first growing year, the different crops are ready to be rotated to their successive plots. Crop rotation works best when done in this order: Light feeders > Heavy feeders > Root crops > Legumes. After four growing cycles, you will be back to where you started.
*Tip: If you do not grow vegetables of a certain group, plant cover crops like clover or legumes. This will reduce soil compaction, improve drainage, add fertility and suppress weeds.
Crop rotation is not a new trend and has been implemented for centuries. The yield and quality of your crops can significantly increase if grown in this crop follow-up pattern.
To start crop rotation in your own garden, follow this easy How-To Guide!