Sugarcane Irrigation

Sugarcane (Saccharum officinarum) is a vital cash crop, playing a significant role in the world’s economy. It is widely cultivated in tropical and subtropical regions, primarily for the production of sugar, ethanol, and other by-products. Efficient irrigation practices are essential for maximizing sugarcane yield and ensuring sustainable production. This article aims to provide a comprehensive guide on sugarcane crop irrigation, discussing its importance, methods, and best practices.

Why is Irrigation Important in Sugarcane Grow?

Water Requirement

Sugarcane is a water-intensive crop, requiring a consistent supply of water throughout its growth stages. Irrigation ensures adequate moisture levels in the soil, promoting healthy crop development and high yields. 

Although that might be true for every crop out there, when it comes to sugarcane, there are specific nuances that must be taken into account.

Ratoon health and number

After a sugarcane field is planted for the first time, it continues to exist and re-emerge from its root stalks, called ratoons. In the same way, a growing cycle from ratoons can also be called ratoon. Leaving the field and the ratoons to the mercy of nature might compromise substantially the ratoon’s health and number of seasons it provides.

Plant nutrition

An irrigation system is not only a way to deliver water to the plants, it is also a wonderful tool for delivering plant nutrients directly to the root zone. It is much harder to deliver plant nutrients accurately and efficiently without the help of an irrigation system.

Drip irrigation, for example, is a wonderful way to deliver the right nutrients in the right ratio at exactly the right time and quantity directly to the soil, without even wetting the foliage.

Commercial cane sugar (CCS) vs yield balance

The profit a sugarcane grower can make depends on the content of sugar that can ultimately be produced. Raising the sugar content in the plants is therefore paramount. However, having higher yields in this case does not necessarily mean having a higher sugar content. In this crop, the yield can actually come at the expense of sugar content within the plant tissue. Without controlled irrigation, this delicate balance can get out of hand. That is why a proper irrigation system is so important in sugarcane cultivation.

Sugarcane Irrigation Methods

Surface Irrigation

Surface irrigation, also called flood irrigation, is the traditional method, involving the distribution of water over the soil surface using gravity. This method is further divided into three subcategories: furrow irrigation, border irrigation and basin irrigation. In order to even consider this method of irrigation, the field has to be surfaced and leveled. The extremely low water use efficiency of flood irrigation is only matched by its low cost.

Flooding or furrow irrigation tends to bring the crop to extremities. When flooded, the field gets saturated. Anoxia conditions are often formed and heavy leaching of water and nutrients occurs. After flooding, since a substantial amount of water is involved, the tendency is to wait as long as possible before flooding again. This means water stress is usually the case. Whenever plants go through these extreme conditions, their production is impaired, and eventually, their yield.

Sprinkler Irrigation

Sprinkler irrigation involves the distribution of water through a system of pipes and sprinklers, mimicking natural rainfall. This method is ideal for some crops under certain circumstances, but for sugarcane cultivation, pivot irrigation might not be the best solution. 

Central pivot irrigation is sensitive to wind. Under windy conditions, water distribution uniformity might be impaired. Furthermore, central pivot, by its very nature, cannot irrigate the whole field, and unfortunately around 20 per cent of the field is missed. 

When pest and disease control is the issue, wetting the whole upper part of the plants might make it difficult to maintain a disease-free stand. Rises in humidity might encourage inoculation. 

When sprinkler irrigation is used, the whole area of the field is irrigated, with no consideration as to where the actual rows of plants are and where the actual relevant root zone is, reducing water conservation.

Drip Irrigation

Drip irrigation is a highly efficient method that delivers water directly to the plant’s root zone through a network of emitters, tubes, and pipes. This method minimizes water loss and promotes uniform water distribution, resulting in improved crop yield and water use efficiency. Drip irrigation is particularly advantageous when it comes to sugarcane. 

Drip Irrigation Benefits for Sugarcane Growth

Drip irrigation has emerged as one of the most efficient methods for irrigating sugarcane crops. It offers numerous benefits, contributing to higher yields and more sustainable production.

Water Use Efficiency

Drip irrigation delivers water directly to the plant’s root zone, minimizing evaporation and runoff losses. This precise application of water ensures that the crop receives the required moisture while conserving water resources. In comparison to traditional irrigation methods, drip irrigation can save 40–60 per cent of water.

Enhanced Nutrient Uptake

Drip irrigation allows for more precise control of nutrient application through fertigation. By delivering nutrients directly to the root zone, it ensures efficient nutrient uptake and reduces the risk of nutrient leaching. This targeted approach can lead to better crop growth and higher yields, while saving on fertilizers and reducing chemical leaching.

Improved Sugarcane Crop Yield

The uniform distribution of water and nutrients provided by drip irrigation promotes consistent growth and development of sugarcane plants. Studies have shown that drip irrigation can result in yield increases of 20–50 per cent compared to traditional irrigation methods, and much more when compared to rain fed cultivation. 

Lower Disease and Pest Pressure

Drip irrigation reduces the amount of surface moisture on the sugarcane plants, which can help lower disease and pest pressure. Diseases and pests that thrive in wet conditions are less likely to infest sugarcane crops irrigated using drip systems, compared to any other kinds of overhead irrigation, leading to healthier plants and reduced reliance on chemical control measures.

Adaptability to Various Soil Types

Drip irrigation systems can be customized to suit various soil types and topographies, making them a versatile option for sugarcane cultivation. By adjusting the emitter spacing, flow rate, and system pressure, farmers can tailor the irrigation system to meet the specific needs of their crop and soil conditions.

Adaptability to Various Soil Types

Drip irrigation systems are typically more labor-efficient than traditional irrigation methods, as they require less manual intervention for operation and maintenance. Additionally, drip systems often operate at lower pressures, reducing energy consumption and associated costs.

The following table shows the impact of drip irrigation over flood (furrow) for sugar production in Australia:

Comparison of Sucrose Yield – Furrow vs Drip Irrigation

Best Practices for Sugarcane Crop Irrigation

To maximize sugarcane yield and promote sustainable production, consider the following best practices for irrigation:

• Soil Moisture Monitoring: Regularly monitor soil moisture levels to determine the appropriate irrigation schedule and avoid overwatering or underwatering.
• Irrigation Scheduling: Plan your irrigation schedule according to the crop’s growth stages, climatic conditions, and soil type to ensure optimal water usage.
• Water Conservation: Implement water conservation techniques such as mulching, rainwater harvesting, and using efficient irrigation methods to minimize water wastage.
• Maintenance: Regularly inspect and maintain your irrigation system to ensure its efficiency and prevent leaks or malfunctions.
• Fertilizer Management: Incorporate fertigation (applying fertilizers through the irrigation system) to improve nutrient uptake and reduce the risk of nutrient leaching.

A well-designed drip irrigation system can make the entire water and nutrition process easier and more effective with benefits including more constant yield, reduced water use and lower operation and labor costs by applying water in consistent, precise quantities that leads to the optimum balance of yield (tonnage) and CCS (sugar content). Add in automated fertilizer application and you have a fully streamlined production process that will provide the best payback at harvest.

A typical sugarcane drip irrigation installation features SDI.

Rivulis has the expertise and broad product portfolio, including drip line, drip tape, pumps, filters, valves, automation, and fertigation, to customize a complete sugarcane solution tailored to your particular needs.