Crop rotation is based on the principle that vegetables from the same group should not be planted in the same place year after year, but should be rotated to new soil each year. The vegetables we grow can be divided into four main groups namely, heavy feeders, light feeders, root crops and legumes. Plants in these groups share similar characteristics and often suffer from the same pests or diseases. By rotating these crops each year prevents the build-up of soil-borne pests and diseases and improves soil health and fertility by avoiding total nutrient depletion. In this how-to guide, we will show you how to group different vegetables and how to apply crop rotation to your own vegetable garden.
1. Divide the garden into plots
Divide your growing space into four distinct areas, each area dedicated to one of the four vegetable groups.
2. Group crops
After you have identified the crops you want to grow, group the plants according to the four main groups i.e. Heavy feeders, light feeders, legumes and root crops (as shown in steps 3 - 6).
3. Group 1: Light feeders
Light feeders include crops like salads, spinach, kale and other leafy greens. These crops need a good amount of nitrogen to produce a harvest, e.g. lettuce, kale, spinach, chard, cabbage, cauliflower, as well as herbs
4. Group 2: Heavy feeders
Heavy feeders include crops like eggplant, pumpkins and tomatoes. These crops need a good dose of phosphorous and small amounts of nitrogen to produce fruit.
5. Group 3: Root crops
Root crops are potassium-hungry and include crops like onions, carrots, beetroot and radishes. If pieces of the underground storage organs remain behind in the soil it can lead to soil-borne diseases if replanted in the same soil year after year.
6. Group 4: Legume crops
Legumes include beans, lupins and peas. These are excellent nitrogen fixers since they have a symbiotic relationship with micro-organisms to feed and condition the soil.
7. Outline your plan
Choose which plot each group will go in. Per example: Frame 1 (Top left): Heavy feeders - Squash, watermelon and tomatoes Frame 2 (Top right): Light feeders - Spinach, kale and cauliflower Frame 3 (Bottom left): Legume - Sweet peas Frame 4: (Bottom right): Root crop - Carrots Tip: Plant groupings in a clockwise manner to keep track of rotation.
8. Stick to the plan
This year you will rotate so that the heavy feeder crops goes where last year’s light feeder crops were, root crops go where last year’s light feeder crop was and so forth. Next year you will rotate your crop again, and after four cycles of rotation, you will be back to where you first started.