Growing Soya Beans 101

1. Types of Soya Cultivars Available

a. Determinate vs. Indeterminate

Soya bean seed has two types of cultivars which is determinate and indeterminate.

Determinate - Will grow vegetatively for about six weeks, then begin their reproductive stage which is flowering, pod development, seed development and maturity having put on 12 leaves no further new leaves are produced on the main stem. Therefore, in simple terms we can conclude to say determinate cultivar have a specific height they tend to reach and cannot grow further from there.

Whereas indeterminate grow vegetatively for about six weeks, then begin their reproductive stage when the main stem is about 10 leaves, and continue to grow and produce another five to seven leaves. Therefore, in simple terms these types of cultivar do not have a specific height, they tend to grow taller depending on how you manage them.

Indeterminate cultivars tend to grow taller than determinate cultivars.

b. Maturity

In soya beans we only have medium to late maturity variety and the common ones are Dina and Spike which take about 135 days to mature.

2. Land Preparation

a. Conventional - this involves mechanical operation or use of draft animals to plough, disc and rip the soil.

b. Conversation - this is a method of soil cultivation that leaves the previous year’s crop residue in fields before and after planting the next crop to reduce soil erosion and runoff. It’s mainly involves less soil surface disturbance which we refer to as zero tillage. This method will require application of more herbicides.

c. Minimum Tillage – this is a soil conversation system with a goal of minimum soil manipulation which is less soil disturbance, where the soil is not turned over. Which in return will reduce, causes build-up of organic matter in the soil, hence betters physical soil fertility.

3. Application of Fertilizers (D-compound)

Soya beans at planting, a farmer can apply D-compound, by broadcasting on the planted field, 2 bags are enough to cover a ha. Farmers can skip this stage if they wish to and use boosters.

Boosters can be applied in two weeks interval at vegetative stage, two sprays will be enough .You will also need to spray a booster at reproductive stage (flowering stage), two sprays will be enough in two weeks interval. Fertigreen is a well recommended booster for soya beans, you can find it in all Agricrop outlets.

4. Inoculation

Before the seed is planted it is important to add an inoculant, this inoculant will assist the crop make its own nitrogen through a bacteria known as rhizobium, this will in turn benefit the crop and fix nitrogen into the soil.

5. Weed Management

Weeds are unwanted crops in the field, therefore it is important that they are eliminated in order to avoid competition of nutrient with your crop. Weeds have a high affinity for nutrients, once allowed to grow in your field they will benefit from all the nutrients you will be giving the crop. In the end they will cause the crop to be stressed, fail to acquire water, air, sunlight and enjoy the nutrient from the soil. This will then result in an unhealthy crop which will give you low yields.

How do to we ensure that weeds do not compete for nutrients with our crop?

This can be done by application of herbicides or weeding if it’s not a big portion. For herbicides we have selective herbicides and non-selective herbicides.

Non-selective herbicides - these are herbicides that kill weeds as well as desired plants. In short they kill any vegetation they come into contact with e.g. Roar extra which is systematic and paraquat which is a contact herbicide. You can purchase theses herbicides at all of our Agricrop outlet, contact Henry on +260-975-683867.

Selective herbicides – these are herbicides which are tailor-made to kill only unwanted material and leave out the desired crop i.e. these herbicides will only kill weeds and leave out your desired crop e.g. for soya beans Agricrop has Foquiz and limit.

6. Insect and Disease Management

a. Insect

Ensure to scout for insects immediately after crop emerges, and make spraying decisions. Common insects found in soya beans include; Bean leaf beetles, soybeans aphids, fall armyworms, stink bugs, cutworms grasshopper etc. These vary from season to season and from farm to farm. Available Agricrop insecticides include cyfos, methomyl, elufen and Acetamiprid.

b. Disease

Ensure to scout for diseases once the crop emerges and make spraying decision, common diseases found in soya beans include: Bacterial pustule, Fusarium wilt, powdery mildew, and Septoria brown spot etc. It is very important to at least do one fungi spray as a preventive in your soya crop.

For soya beans growing and purchase of inputs, contact Agronomist H. Kanyimbo on +260-975-683867.