Compiled by: Etienne Bruwer, Ruan Gagiano, and Renier Bothma, Agronomists at Kynoch

Dryland agriculture, where crops rely on natural rainfall instead of irrigation, demands meticulous soil management and precise nutrient strategies—particularly for maize and soybean production. A critical framework to achieve optimal yields is the 4Rs of nutrient management: applying the right source, at the right rate, at the right time, and in the right place. Additionally, managing soil compaction—a prevalent issue in dryland systems—is essential to ensure sustainable crop performance.

The 4Rs of Nutrient Management

1. Right Source

Selecting the appropriate fertiliser type is vital for maximising nutrient efficiency. Maize thrives with nitrogen-rich fertilisers, whereas soybeans—being nitrogen-fixing crops—require sufficient phosphorus and potassium to reach their full potential.

For Maize: Nitrogen-based fertilisers, such as coated urea, are recommended for their ability to minimise nutrient losses due to volatilisation.

For Soybeans: Phosphorus and potassium applications are essential for promoting robust growth. Additionally, inoculants can enhance nitrogen fixation, which plays a key role in supporting plant health and productivity.

2. Right Rate

The fertiliser application rate should be based on soil test results to address nutrient deficiencies effectively.

For Maize: Fertiliser quantities must be adjusted according to soil test data, historical yield patterns, and projected rainfall.

For Soybeans: Although soybeans require less nitrogen due to biological fixation, soil analysis should inform the optimal application of phosphorus and potassium to support growth and yield.

3. Right Time

Applying fertiliser at the appropriate time is particularly important in dryland systems, where water availability may vary.

For Maize: Split nitrogen applications—first at planting and later during key growth stages—ensure that nutrients are available when the plant needs them most, maximising uptake efficiency.

For Soybeans: Fertiliser should ideally be applied before or early in the growing season to ensure that roots can access nutrients crucial for establishment and development.

4. Right Place

Correct placement of fertiliser minimises nutrient loss and ensures efficient delivery to the root zone.

For Maize: Placing fertiliser close to the roots reduces losses from volatilisation or runoff, especially under dry conditions.

For Soybeans: Phosphorus and potassium should be positioned near the roots to ensure these essential nutrients are readily available as the plant matures.

Addressing Soil Compaction

Soil compaction poses a significant challenge in dryland systems, as it limits root penetration, impedes water infiltration, and reduces airflow in the soil profile. Managing compaction effectively is critical for improving water uptake and maintaining optimal yields.

Strategies to Prevent and Mitigate Soil Compaction

• Reduce Tillage: Minimising tillage preserves soil structure, facilitating water retention and promoting healthy root growth.
• Implement Cover Crops: Deep-rooted cover crops such as radishes naturally break up compacted layers while improving water infiltration and moisture conservation.
• Adopt Controlled Traffic Farming (CTF): Restricting machinery to specific paths prevents widespread compaction, allowing better root development in non-compacted zones.
• Subsoiling: In severe cases, subsoiling can help fracture compacted layers; however, this practice must be applied cautiously to avoid disrupting the soil’s moisture-holding capacity.
• Incorporate Organic Matter: Adding organic material, such as crop residues or compost, enhances soil structure and reduces compaction. Organic matter also improves the soil’s water-holding capacity, which is especially beneficial in dryland systems.

Conclusion

Achieving high yields in dryland maize and soybean production requires a dual focus on nutrient management and soil health. By applying the 4Rs—right source, rate, timing, and placement—farmers can optimise fertiliser efficiency. At the same time, managing soil compaction through reduced tillage, cover crops, and organic matter enrichment enhances soil resilience, ensuring sustained productivity under challenging environmental conditions.

The post Best Practices for Dryland Maize and Soybean Cultivation first appeared on Kynoch Fertilizer.

By Renier Bothma, Ruan Gagiano and Etienne Bruwer (Kynoch Fertilizer)

Dryland crop production is subject to extreme climatic conditions, along with the inherent risks that come with it. According to Grain SA’s (2024) 6th production estimate, maize and soybeans are expected to dominate grain production areas in the 2024/2025 season. Therefore, it is critical to make the right product choice in terms of fertilisation for soybeans and maize.

The ideal planting time for maize and soybeans can vary from one week to a month, depending on the season. External factors can suppress crop growth, but by using fertiliser “on” the seed (“Pop-up”), the negative effects of these factors can be significantly reduced. One product specifically designed for this purpose is KynoPop®. Micronutrients such as zinc, iron, manganese, copper, boron, and molybdenum are essential for the growth of maize and soybeans, playing key roles in processes like enzyme function and photosynthesis. The product contains all the important macro- and micronutrients that a young seedling needs to improve growth and reduce overall plant stress.

An additional supplement that can further help reduce stress is the application of KynoFulvate Yellow® and KynoKelp® in the planting furrow during planting. Both products are in liquid form, making them easy to mix with KynoPop®. KynoFulvate Yellow® is a fulvic acid that improves the availability of nutrients to the plant and can also serve as a food source for microorganisms. KynoKelp® is a seaweed extract containing natural macro- and micronutrients, which is excellent for promoting root development. It is derived from the kelp species Ecklonia maxima. All three products are locally manufactured and address important plant needs when used in combination.

Kynoch Fertilizer’s Ultra® range offers an alternative solution for micronutrient and macronutrient feeding! Since some micronutrients are less mobile in the soil, positioning them near the roots ensures that plants can optimally absorb the nutrients. The band placement of the Ultra® range reduces the potential lock-up of nutrients due to soil interactions.

Foliar sprays of micronutrients have their place in crop nutrition, but can sometimes vary significantly in terms of effectiveness. Nutrients applied to leaves can be washed off or may not be consistently absorbed, making band placement a more stable and efficient approach. Local application of micronutrients in the root zone is also more cost-effective, as it reduces nutrient losses and often requires fewer applications (Nathan et al., 2011).

When discussing macronutrient feeding, nitrogen volatilisation is one of the biggest challenges in a dryland production system in South Africa. According to Botha (1987), high rates of volatilisation are common in soils with low clay content, due to fluctuating pH levels. Other factors that have a significant impact on volatilisation include wind speed and temperature, both of which typically vary in dryland crop production. Kynoch Fertilizer’s KynoPlus® range offers a solution for reduced volatilisation through the incorporation of a urease inhibitor.

Soybeans have a low nitrogen requirement because they host a nitrogen-fixing bacterium, Rhizobium, which supplies nitrogen to the plant. Maize, on the other hand, has a high nitrogen requirement, and this need must be supplemented at various stages. Most nitrogen applications occur during pre-planting and topdressing, where it is critical to minimise nitrogen losses by using the KynoPlus® range. A wide variety of planting mixtures, as well as topdressing products, are available in the KynoPlus® option.

Kynoch Fertilizer offers effective solutions to reduce crop stress through a range of products formulated for dryland crop production. Contact your nearest Kynoch agent or agronomist today to find out how we can meet your needs!

References:

Botha, A.D.P. 1987. Nitrogen losses from urea, UAN and LAN when applied to four different soils, South African Journal of Plant and Soil, 4(1): 43-46.

Grain SA. 2024. Production Estimates. [https://www.grainsa.co.za/report-documents?cat=27] Date of access: 30 Aug. 2024.

Nathan, D., Mueller, A., Dorivar, A. 2011. Micronutrients As Starter and Foliar Application For Corn And Soybean. Available at: [https://www.extension.iastate.edu/Pages/eccrops/nceisfc11/8.pdf] Date of access: 30 Sept. 2024.

USDA (United States Department of Agriculture). 2024. [https://apps.fas.usda.gov/newgainapi/api/Report/DownloadReportByFileName?fileName=Grain%20and%20Feed%20Annual_Pretoria_South%20Africa%20-%20Republic%20of_SF2024-0006] Date of access: 30 Aug. 2024.

Contact us today to get tailored advice for your needs: 011 317 2000 or contact one of our regional managers directly: here

KynoPop® K9101 (Act 36 of 1947)

KynoFulvate Yellow® M261 (Act 36 of 1947) 

KynoKelp® M314 (Act 36 of 1947) 

Ultra Starter® K9001 (Act 36 of 1947) 

KynoPlus® K8024 (Act 36 of 1947) 

The post Optimise Dryland Maize and Soybean Production with Kynoch Fertilizer first appeared on Kynoch Fertilizer.