Crop rotation is one of the oldest and most effective cultural control strategies. It means the planned order of specific crops planted on the same field. It also means that the succeeding crop belongs to a different family than the previous one. The planned rotation may vary from 2 or 3 years or longer period.
Some insect pests and disease-causing organisms are hosts’ specific. For example, rice stem borer feeds mostly on rice. If you don’t rotate rice with other crops belonging to a different family, the problem continues as food is always available to the pest. However, if you plant legume as the next crop, then corn, then beans, then bulbs, the insect pest will likely die due to the absence of food.
Why Crop Rotation Is Important?
- First of all, it prevents soil depletion
- Crop rotation improves the fertility of the soil and hence, brings about an increase in the production of food grains.
- Reduces soil erosion
- Controls insect/mite pests. Crop rotation as a means to control insect pests is most effective when the pests are present before the crop is planted have no wide range of host crops; attack only annual/biennial crops, and do not have the ability to fly from one field to another.
- Reduces reliance on synthetic chemicals
- Reduces the pests’ build-up
- Prevents diseases
- Crop rotation adds diversity to an operation.
- Finally, it helps to control weeds
Advantages Of Crop Rotation
There are many benefits to crop rotation including the suppression of diseases, insects, and weeds. In addition, crop rotation improves soil fertility because it is allowed to replenish naturally and soil structure improves because of the alternating between deep rooted and fibrous rooted crops.
Crops within a family tend to be susceptible to the same pests, therefore rotation of non-susceptible crops (or groups) for several years allows all plant material to decompose and pest cycles to become broken. Without the presence of susceptible plant material, the number of disease and insect organisms will begin to diminish.
Crop rotation aids in weed control because the growth habit of each crop differs, which causes a decrease in a weeds ability to compete for space. Also, tillage practices and timing are different for dissimilar crops resulting in a decrease in the weeds ability to permanently establish. Another benefit of crop rotation for weed management purposes is with certain crops, there is a better chance at controlling different weeds. For example, in a broadleaf crop, grass control will be easier because of the use of grass killing herbicides and visa verse.
How To Schedule A Crop Rotation
To create a crop rotation schedule, there are several things you must consider. It includes types of vegetables grown, the size of the root, the size of planting rows, amount of fertility required for the crop and how much organic matter is left in the soil by the crop. Start designing the crop rotation by making a list of all vegetables to be grown. And you can group them together by botanical relationship (e.g. Brassicaceae, Solanaceae, Alliaceae). Each year, change the location of the entire group within the field. This way, the same crop group will not be planted on the same piece of land two years in a row.
Secondly, consider the size of the root system of the crop to be grown. Deep-rooted plants will help to break up the soil, while shallow-rooted crops will not.
Thirdly, consider the size of the plant rows. Wide rows will allow for more weed seeds to germinate. However, tillage equipment may be able to go through them with more ease than in narrow
The fourth consideration is whether you will plant a heavy feeder crop. A heavy feeder will deplete the soil of nutrients quicker than a nonheavy feeder.
The final consideration for a crop rotation is whether the crop will leave a lot of organic matter in the soil. Leaving organic matter behind is beneficial for replenishing the soil of nutrients lost to the crop.
Useful Tips For Crop Rotation
- Know the family where your crops belong to make sure that you plant on the next cropping a crop that belongs to a different family than the previous one.
- Make a list of the crops you want to grow by also taken into consideration the market’s demand for your produce. For example, plant leafy vegetable on the first cropping season, next fruit vegetables, then root crops, then legumes, then small grains.
- Grow legumes before grains or cereals.
- Practice green manuring.
- Finally, I must advise always keep farm records.