Soybeans (glycine max) production
Site selection
Soybeans is a sunlight-loving plant that grows in all parts of Ghana but is predominantly grown in the Sudan savanna, the Guinea savanna, and the transitional ecological zones of Ghana. Study your rain fall pattern and plant your soybeans to at least get 90 days of good moisture to meet all its water requirements for better pod filling. You must avoid clayey soils where waterlogging occurs. Select well-draining soils.
Land preparation
Plough as early as May ending if you can afford ploughing and harrowing. Harrow the first week of June and plant immediately; there is good moisture for planting, especially in the Sudan and Savanna ecological zones. We will be expecting a dry season from the middle of October to November, which is ideal for harvesting.
The transitional area should start ploughing and harrowing in mid-June and start planting in the first week of July to end. The dry season normally start middle of November to first week of December and is ideal to start harvesting
Note: It is very important to plant soybeans to meet their water requirement and not to plant too early for maturity and drying to coincide with rainfall. This can cause moulding and total loss to the farmer.
Choice of variety
As a farmer, select varieties that are well adapted to your environment and climate. Select soybeans based on maturity. If you must use seeds from your previous farms, make sure you store them very well and know the trace and variety. It will be a risk if you buy seeds from open market grains if you cannot determine the variety. There is a likelihood of buying variety that shatters, and you can lose your yields when not harvested early. If you are early with your land preparation, you can choose a late-maturing variety.
However, if you are late do not risk planting late-maturing variety because the rains, which we do not control can stop at any time and are expectedly and is prudent for every farmer to choose early-maturing variety when the farmer is late in land preparation
Seed preparation for planting
Buy your seeds from a reputable company, make sure you know your variety, and do a germination test when about to prepare your land.
Inoculating your seeds is a requirement and the cheaper source of Nitrogen. Every farmer should get inoculants
Planting
Soybeans requires more nitrogen, and as a legume crop that can fix its own nitrogen, it is a requirement for all farmers to inoculate their seeds to fix free and cheaper nitrogen into the soil for the use of the plant.
Make sure you buy inoculant from a good source. Nitrogen is supplied to soybeans mainly by nitrogen fixation. Nitrogen fixation is the result of a symbiotic relationship between the soil-born bacteria Bradyrhizobium and soybean root. In this symbiotic relationship, carbohydrates and minerals are supplied to the bacteria by the plant, and the bacteria transform N2 gas from the atmosphere into ammonium-N for use by the plant.
Fields that never had soybeans in them or have not had soybeans in them for several years will have no natural Bradyrhizobium japonicum, or levels will be too low for adequate infection and nodulation. In these instances, an inoculant seed treatment is necessary. Both liquid and dry formulations are available, but bacteria are living organisms; care must be taken to protect them from high temperatures that may kill them. If the plants are inoculated, additional nitrogen application is not recommended.
Soybeans should be planted in order for the maturity and harvest to coincide with the dry season. The recommended date for planting soybeans in different ecological zones in Ghana;
Derived savanna/southern guinea savanna: Early June–Early July
Northern Guinea savanna: Mid-June–Early July
Sudan savanna: Early July
Transitional ecological zone: Mid-July-Early August
Seed rate
The required seed rate for optimal population (250,000–300,000 plants) per ha (10,000 m2) is about 40–50 kg of seeds per ha. Most soybeans size ranges from 12.6 to 18.9 g/100 seeds
Plant spacing
Sow soybeans by hand, by planter, or by drilling. Plant in lines to make the control of weeds and pests easy. If you are going by broadcasting, it should not exceed 30 plants per meter square. When broadcasting, you have to plough and allow rain to fall on it; broadcast properly and uniformly before harrowing, not deep into the soil. Seeds will be covered for easy germination.
If using any method of planting, scout around your field, and if you see poor germination, immediately do filling in. Plant population is an important factor in yield determination and has to be taken seriously.
If planting, do it 2-3 seeds per hole at a spacing of 75 cm between rows and 10 cm within the row.
You can also plant 2 seeds in a hole, 40 cm between rows and 20 cm within rows.
Fertiliser application
Do not assume that, because soybean is a legume crop, it does not require fertiliser.
Note that, every crop has its own nutrients requirement to gives out its best yield and is the sole responsibility of the farmer to provide the required nutrients the crop to give a better yield
As farmers, we try as much as possible to reduce the cost of production but have to put in the effort to treat the plant with available resources for higher productivity and to at least attain the average yield from the crop. I indicated earlier that the bacteria in the inoculant will provide the needed nitrogen for the soybeans; we, however, need to make provisions for other essential nutrient elements.
Soybeans require 14 mineral nutrients for growth and for better yields, and there are as follows:
Nitrogen, phosphorus, potassium, sulphur, calcium, manganese, magnesium, copper, iron, zinc, boron, chloride, molybdenum, and nickel. Most soils can provide adequate amounts of minor nutrients, but growers need to pay attention to plants needs with regards to NPK S and Fe.
The best soil fertility management of crops always begins with regular soil testing. Soil testing is a valuable and inexpensive tool for ascertaining the nutrient and PH, buffer PH.
Soybeans are not high feeders but will require to meet their nutrient requirements to give out the best. It is off this view, and with commercial farmers and smallholder farmers, Demeter Ghana, with its team of agronomists, continues to make demo fields in northern Ghana to always come up with the most cost-effective nutrient treatment for soybeans that can provide the most mobile and major nutrients element for the soybean plant. No crop can perform well without an adequate supply of any of the major nutrients (nitrogen, potassium, and phosphorus). Rizoliq soy inoculant is enough to facilitate nitrogen fixation in soybean; monopotassium phosphate (soluble folia fertiliser, MKP 0:52:34) sprayed after 3 weeks and 6 weeks after germination is enough to meet the soybean requirement for potassium and phosphorus. After this treatment, the soybean crop meets its nitrogen, potassium, and phosphorus at a good cost, which is effective for the farmer with good results.
The minor nutrients are as important as the major but are required by crops in smaller quantities and are mostly supplied by the soil to the soybean crop. In extreme cases, soil analysis can show some minor nutrients are very low in the soil. This is where Demeter Ghana introduce a premium folium fertilizer Omex starter pro (NPK 24:24:18 + TE) and Bloom Bost (18% N, 22% CaO + TE), a formulation of both major and mino nutrients for effective nutrients supply
Soil PH
Soil pH is important because it has a direct effect on the availability of nutrients to the plant in the soil. The pH of soil is a measure of the acidity, or concentration, of hydrogen ions in the soil solution. Many chemicals and biological processes in the soil are affected by PH. Maintaining PH in a proper range will maximise the efficacy of other crop inputs and decrease the risks of yield losses. The optimal PH range for maximizing soybeans yield is 6.0 to 6.8 (in mineral soils)
Weed control
Manual weed control
Weed your field about 2 weeks after planting and again 2 weeks later (4-5) weeks after planting. Avoid weeding immediately after rain.
Chemical weed control
Weeds are strong competitors in every crop; do not allow them to overgrow. Control weeds at the tender stage when they are at the 2-4 four-leaf stage for easy control.
Herbicides, when used properly, can effectively control weeds in soybeans. The choice of the herbicide depends on the predominant weed species on the field and the availability of per-emergence or post-emergence weed control in soybeans.
Insects’ pests and their control
From flowering onwards, soybeans become attractive to pod-sucking bugs that can cause serious reductions in grain yield and quality. Therefore, the crop should be protected at that stage for optimum yield.
Harvesting and post-Harvest handling
Soybeans mature within 3-4 months after planting and require timely harvesting to check excessive yield loss. It is recommended that soybeans be harvested when about 85% of pods have turned brown for the non-shattering variety and 80% for the shattering variety. Stack them closely and allow them to dry in the open for 2 weeks before threshing.
Threshing soybeans
Thresh manually or mechanically as soon as possible. Avoid stones and dry matter in soybeans to enable you to get a premium price and bargaining power.
Finally, join the Ghana Soybeans Farmers and Aggregators Association to get the latest updates on the best production methods from our technical team and control your production with market.
