In organic horticulture an optimal application of organic fertilizers in combination with a sophisticated irrigation is of prime importance to safeguard a good nutrition of the crop and avoid losses of nutrients to the environment. In ECONUTRI two tools have been developed to optimise fertilisation and one tool has been designed to improve irrigation practices.

1. EKOteelt

Short description of the technology

The EKOteelt is a Decision Support System (DSS) for organic greenhouse vegetable growers. Based on the “Bemestingsrichtlijn EKO,” the DSS has been updated as a web-based tool that helps growers manage their nutrient use more effectively. It estimates the nutrient uptake by crops and the release of elements like nitrogen (N), potassium (K), and phosphorus (P) from applied manure and composts. This system gives growers insights into nutrient dynamics, enabling them to make informed decisions based on the type of manure used.

Innovative Features

The new DSS version is significantly more user-friendly than its predecessor. It has been transitioned from a static Excel format to a web-based platform. Users can input their specific crop and fertilizer data, store it, and retrieve it later to track nutrient management. The system automatically generates tailored recommendations, and reports can be generated.

Type of Contribution

By optimizing nutrient use, the DSS plays a key role in reducing nutrient losses to the environment, particularly under the guidelines of the Nitrate Directive. As well as show the different requirements of nutrition if practices, like using the extra organic matter from production in addition to the soil, are implemented.

Benefits for farmers, the industry, and the environment

For farmers, the primary benefits include optimized fertilizer use, which can lower costs and improve crop yield quality. From an environmental perspective, the reduced risk of nutrient runoff/leaching protects groundwater flows, aligning with regulations like the Nitrate Directive. Moreover, the platform helps organic farmers show their commitment to sustainable practices

2. DSS for organic soluble fertilizers

Short Description of the Technology

In organic vegetable production, topdressings are not widely used due to the limited availability of organic water-soluble fertilizer, and the difficulty of quantifying an adequate amount of topdressing. To overcome the problems of slow nutrient supply from organic fertilizer and the lack of synchrony of nutrient release with crop nutrient demand, soluble organic fertilizers with high nutrient availability were screened in the ECONUTRI project for their suitability for organic vegetable cultivation in North China.

In this work, CAU developed a DSS to guide the combined use of top dressing of fast-acting soluble organic fertilizer with base applications of traditional organic fertilizer. This DSS uses the model WHCNS (Soil Water Heat Carbon and Nitrogen Simulator) that was originally developed for conventional agricultural systems. For this work, the soil organic nitrogen mineralization parameters were adjusted for the conversion of organic nutrients to inorganic nutrients. The adapted DSS helps to make decisions on fertilsation for organic vegetable production.

The DSS uses nitrogen balance calculations for nitrogen recommendations. The goal is to maintain a quantity of soil buffer inorganic nitrogen. The DSS calculates the amount of applied nitrogen fertilizer to maintain the buffer while achieving the desired yield. The DSS has a database of commercially available organic water-soluble fertilizer and traditional organic fertilizers. Farmers can select organic water-soluble fertilizers from the database according to crop requirements, soil conditions and other commercial issues.

Innovative Features

The nitrogen in manure and/or other organic water-soluble fertilizers applied in organic agriculture needs to be mineralized into inorganic nitrogen for uptake by crops. The conversion efficiency is mainly affected by the form of organic nitrogen and microbial activity. A sub-model was developed in the DSS to describe this nitrogen conversion process. This sub-model was combined with the nitrogen expert recommendation system of the WHCNS model to provide recommendations for the input of organic water-soluble fertilizer selected from the database.

Type of Contribution

The combined use of (a) the WHCNS model incorporating the organic fertilizer sub-model with (b) organic water-soluble fertilizer enables rational quantitative topdressing in the later crop growth stage. This helps overcome the nutrient gap, in late crop growth that is commonly associated with the use of organic manure. The use of this tool will enable a balance between the nitrogen supply and demand in organic vegetable planting, and reduced nitrogen loss caused by excessive fertilizer input in organic agriculture production.

Benefits for farmers, the industry, and the environment

Organic farmers can select various organic water-soluble fertilizers in the database. With the help of the DSS, they can get the corresponding fertilization decisions to increase crop yield, effectively improve fertilizer utilization efficiency, and save costs. To a certain extent, the market demand for organic water-soluble fertilizer will increase which will benefit the organic fertilizer enterprises. In the aspect of environment, the optimization of fertilization strategy could reduce nitrogen loss.

3. Smart Irrigation strategies

Short description

In organic agriculture, it is of paramount importance to employ cultivation practices that maximise agronomic nitrogen use efficiency. In greenhouses, where the water needs of the plants are covered exclusively through irrigation, when drip irrigation is applied, the active root system of the plants develops only in the zone that is moistened by the drippers. Consequently, a substantial part and where plant roots are unlikely to develop. Smart irrigation strategies may serve as a solution to this problem by using portable drippers to manipulate the root system. Portable drippers that are repositioned during crop development could be employed to expand the horizontal area of the root system thereby promoting root elongation and developments into soil areas with an appreciable but underused nutrient supply.

Innovative Features

This technique would not only benefit root growth, that is necessary for optimal water and nutrient uptake but also will enhance crop nutrient use efficiency by optimizing the use of nutrients supplied in organic biomass incorporated as a basal dressing. This practice enhances the mineralization of organic material incorporated during the basal dressing and facilitates the dilution of minerals in the soil solution. Additionally, increased soil moisture levels will guide tomato roots toward nutrient-rich areas.

Type of Contribution

This irrigation strategy enhances nutrient use efficiency and productivity in organic tomato cropping systems, fostering more sustainable farming practices. By optimizing water and nutrient management, it leads to higher yields while minimizing resource waste. This approach not only supports the growth of resilient organic crops but also contributes to improved food security. Furthermore, it aligns with the goals of the Green Deal, promoting environmentally responsible farming practices that support long-term agricultural sustainability.

Benefits for farmers, the industry, and the environment

This irrigation strategy can enhance crop yield by up to 15%, with benefits expected primarily during later harvest stages when nutrient levels in the root zone generally decline gradually.