1.2 Contact details of resource persons and institutions involved in the assessment and documentation of the Technology

Name of project which facilitated the documentation/ evaluation of the Technology (if relevant)

OPtimal strategies to retAIN and re-use water and nutrients in small agricultural catchments across different soil-climatic regions in Europe (OPTAIN)

Name of the institution(s) which facilitated the documentation/ evaluation of the Technology (if relevant)

Chamber of Agriculture and Forestry of Slovenia – Institute of Agriculture and Forestry Maribor (KGZS) - Slovenia

1.3 Conditions regarding the use of data documented through WOCAT

The compiler and key resource person(s) accept the conditions regarding the use of data documented through WOCAT:

Yes

1.4 Declaration on sustainability of the described Technology

Is the Technology described here problematic with regard to land degradation, so that it cannot be declared a sustainable land management technology?

No

2.1 Short description of the Technology

Definition of the Technology:

Non-winter-hardy honey-producing cover crops enhance soil fertility, prevent erosion, reduce nutrient leaching, and support biodiversity. These fast-growing, flowering plants are integrated into crop rotation, offering ecological and long-term economic benefits - and are supported by EU agricultural subsidies.

2.2 Detailed description of the Technology

Description:

Cover cropping with non-winter-hardy honey-producing mixtures is expanding on arable land in Slovenia, especially in lowland areas near water protection zones, streams, and other water bodies. These plants are often integrated into crop rotations of both conventional and organic farming systems. Together with winter-hardy cover crops, these mixtures are an essential component of good sustainable land management. Supported by the EU's Common Agricultural Policy through SOPO (Schemes for Climate and Environment) and KOPOP (Agri-Environmental-Climate Payments), this technology promotes sustainable agriculture by improving soil structure and health and preventing nutrient leaching.
Cover crops - also referred to as catch crops or green manures - are fast-growing, plants from various families, mostly legumes, grasses and brassicas. After the main crop harvest, these plants are sown and cover the soil during summer, autumn, and winter. We distinguish between winter-hardy and non-winter-hardy cover crops.
One of the most popular non-winter-hardy mixtures used in Slovenia, includes Egyptian clover (Trifolium alexandrinum), red clover (Trifolium pratense), phacelia (Phacelia tanacetifolia), and niger (Guizotia abyssinica). These species are drought-tolerant, support pollinators, and naturally perish after the first frost, simplifying subsequent soil preparation.
Their main functions are to improve soil fertility, retain moisture, prevent erosion, and reduce nutrient leaching into waterways. The different characteristics of the species in the mixture combine multiple advantages:
- dissimilar root systems extract nutrients from different layers of the soil;
- the various plant species extract different root exudates, which serve as a nutrient source for soil microorganisms;
- compacted soils become loose and of better structure;
- these species combined lead to enriched organic matter and humus;
- flowering species provide forage for pollinators;
- an overall impact is a reduced need for fertilizers and pesticides which in turn enhances water quality and lowers environmental risks;
- the leguminous species in the mixture fix nitrogen from the air, and follow-up crops like maize require less fertilizer, reducing greenhouse gas emissions.
Honey-producing non-winter-hardy mixtures are typically included in multi-year crop rotation plans. Activities involve selecting appropriate plant species/varieties or mixtures or species/varieties based on soil, climate, rotation and function requirements.
Shallow cultivation or direct sowing on well-prepared seedbeds takes place after cereal harvest, generally in July and August, with a recommended seeding rate of 12 kg/ha. Farmers usually avoid additional fertilization, as soil nutrients suffice for the growth of cover crops. Minimal maintenance is needed during growth since these plants suppress weeds and reduce pest pressure. Termination involves natural frost die-off, mulching, rolling, or shallow tillage. Detailed record-keeping ensures compliance with subsidy programs and supports long-term benefits.
Farmers value such cover cropping for its multiple benefits. They very much appreciate the subsidies they get for their additional effort to sow cover crops. However, challenges include higher initial costs, dependency on appropriate weather, complex timing of operations, and potential competition with main crops. Despite these hurdles, many farmers see cover cropping as a critical component of sustainable farming practices.

2.3 Photos of the Technology

2.5 Country/ region/ locations where the Technology has been applied and which are covered by this assessment

2.6 Date of implementation

Indicate year of implementation:

2020

If precise year is not known, indicate approximate date:

• less than 10 years ago (recently)

2.7 Introduction of the Technology

Specify how the Technology was introduced:

• through land users' innovation
• during experiments/ research

Comments (type of project, etc.):

The farmer adopted cover cropping as part of his transition to low-tillage farming, supported by experimentation and guidance from the public advisory service. The measure, backed by CAP subsidies, was adopted after research and experimentation, ensuring its effective integration into his farming system.

3.1 Main purpose(s) of the Technology

• improve production
• reduce, prevent, restore land degradation
• conserve ecosystem
• protect a watershed/ downstream areas – in combination with other Technologies
• preserve/ improve biodiversity

3.2 Current land use type(s) where the Technology is applied

Land use mixed within the same land unit:

No

3.3 Has land use changed due to the implementation of the Technology?

Has land use changed due to the implementation of the Technology?

• No (Continue with question 3.4)

3.4 Water supply

Water supply for the land on which the Technology is applied:

• rainfed

3.5 SLM group to which the Technology belongs

• improved ground/ vegetation cover
• minimal soil disturbance
• integrated soil fertility management

3.6 SLM measures comprising the Technology

3.7 Main types of land degradation addressed by the Technology

3.8 Prevention, reduction, or restoration of land degradation

Specify the goal of the Technology with regard to land degradation:

• prevent land degradation
• reduce land degradation

4.1 Technical drawing of the Technology

4.2 General information regarding the calculation of inputs and costs

Specify how costs and inputs were calculated:

• per Technology area

other/ national currency (specify):

EUR

If relevant, indicate exchange rate from USD to local currency (e.g. 1 USD = 79.9 Brazilian Real): 1 USD =:

0.85

4.3 Establishment activities

	Activity	Timing (season)
1.	Purchase of a disc harrow with cover crops seed drill	1st year

Comments:

The use of a disc harrow with a cover crop seed drill can support soil preparation and sowing, but it is not strictly necessary. Many farmers use other types of harrows and seeders, which may be more cost-effective or already available on the farm. In some cases, such equipment is shared or acquired through collective investment. While the typical depreciation period for this type of machinery is around 12 years, it is often used for 20 to 30 years, or as long as it remains functional and economically viable.

4.4 Costs and inputs needed for establishment

	Specify input	Unit	Quantity	Costs per Unit	Total costs per input	% of costs borne by land users
Equipment	Disc harrow with cover crops seed drill	piece	1.0	20000.0	20000.0	70.0
Total costs for establishment of the Technology					20000.0
Total costs for establishment of the Technology in USD					23529.41

If land user bore less than 100% of costs, indicate who covered the remaining costs:

Part of the agricultural machinery intended for the implementation of environmental measures can be funded through non-repayable grants from European and national funds under the CAP.

Comments:

The cost of such machinery is a key factor, as equipment like a disc harrow with a seed drill can be expensive. However, it should last for 20 years (or more). Furthermore, it is not strictly necessary, many farmers use simpler or existing machinery, and shared or collective investment is also common.

4.5 Maintenance/ recurrent activities

	Activity	Timing/ frequency
1.	Variable costs of honey-producing non-winter-hardy cover crops	Every year.

Comments:

Variable costs represent the total production expenses for sowing the mixture, including seeds, machinery and labor costs and financing.

4.6 Costs and inputs needed for maintenance/ recurrent activities (per year)

	Specify input	Unit	Quantity	Costs per Unit	Total costs per input	% of costs borne by land users
Labour	Work with machines	hour	52.0	9.0	468.0	100.0
Equipment	Seedbed preparation and sowing	hour	23.0	35.2	809.6	100.0
Equipment	Mulching	hour	29.0	32.0	928.0	100.0
Plant material	Seed	ha	11.44	79.2	906.05	100.0
Other	Financing cost	%	0.03	3089.94	92.7	100.0
Total costs for maintenance of the Technology					3204.35
Total costs for maintenance of the Technology in USD					3769.82

Comments:

The farmer cultivates a total of 28.6 hectares of arable land. The area is theoretically divided into five equal parts, as it follows a 5-year crop rotation system. Additionally, a cover crop is sown after barley and wheat. Therefore, we have accounted for costs on 2/5 of the additional total area.

4.7 Most important factors affecting the costs

Describe the most determinate factors affecting the costs:

The total area is theoretically divided into five equal parts, following the 5-year crop rotation system. However, in practice, this division is not perfectly even. Other important cost factors include variations in input prices (such as seeds, fertilizers, and plant protection products), machinery costs, labor availability, and weather conditions that impact yields and operational efficiency.

5.1 Climate

5.2 Topography

Indicate if the Technology is specifically applied in:

• not relevant

5.3 Soils

5.4 Water availability and quality

Is water salinity a problem?

No

Is flooding of the area occurring?

Yes

Regularity:

episodically

Comments and further specifications on water quality and quantity:

Hydromelioration was carried out in the area, a drainage system and water retention systems (e.g. ponds and basins) were arranged.

5.5 Biodiversity

5.6 Characteristics of land users applying the Technology

5.7 Average area of land used by land users applying the Technology

5.8 Land ownership, land use rights, and water use rights

Land ownership:

• individual, titled

Land use rights:

• leased
• individual

Water use rights:

• communal (organized)

Are land use rights based on a traditional legal system?

No

Specify:

Based on national legal system.

5.9 Access to services and infrastructure

6.1 On-site impacts the Technology has shown

Socio-economic impacts

Production

Income and costs

Ecological impacts

Water cycle/ runoff

Soil

Biodiversity: vegetation, animals

Climate and disaster risk reduction

Specify assessment of on-site impacts (measurements):

The data have not been obtained through specific measurements but rather through a questionnaire with the farmer and insights from other farms and agricultural advisors.

6.2 Off-site impacts the Technology has shown

Specify assessment of off-site impacts (measurements):

The data have not been obtained through specific measurements but rather through a questionnaire with the farmer and insights from other farms and agricultural advisors.

6.3 Exposure and sensitivity of the Technology to gradual climate change and climate-related extremes/ disasters (as perceived by land users)

Gradual climate change

Gradual climate change

	Season	increase or decrease	How does the Technology cope with it?
annual temperature		increase	well
seasonal temperature	summer	increase	well
seasonal temperature	spring	increase	moderately
seasonal temperature	autumn	increase	well
seasonal temperature	winter	increase	moderately
seasonal rainfall	summer	increase	well
seasonal rainfall	spring	increase	moderately
seasonal rainfall	autumn	decrease	well

Climate-related extremes (disasters)

Meteorological disasters

	How does the Technology cope with it?
local rainstorm	well

Climatological disasters

	How does the Technology cope with it?
heatwave	well
drought	well

6.4 Cost-benefit analysis

How do the benefits compare with the establishment costs (from land users’ perspective)?

How do the benefits compare with the maintenance/ recurrent costs (from land users' perspective)?

Comments:

In the short term, establishment costs are high machinery investment, with no direct financial return. However, in the long term, benefits such as improved soil fertility, reduced input costs, and better yields in crop rotation help offset initial expenses. In the short term, maintenance costs, such as seed, labor for sowing and termination, are balanced by reduced expenses on herbicides and fertilizers. Over the long term, cover cropping leads to lower input costs, improved soil health, and better yields in crop rotation

6.5 Adoption of the Technology

• 11-50%

Of all those who have adopted the Technology, how many did so spontaneously, i.e. without receiving any material incentives/ payments?

• 0-10%

6.6 Adaptation

Has the Technology been modified recently to adapt to changing conditions?

Yes

If yes, indicate to which changing conditions it was adapted:

• changing markets

Specify adaptation of the Technology (design, material/ species, etc.):

The composition of the cover crop mix was adjusted to better fit the crop rotation, improving soil fertility and weed suppression.

6.7 Strengths/ advantages/ opportunities of the Technology

Strengths/ advantages/ opportunities in the land user’s view
Improvement of soil fertility (improved soil structure, increased humus - organic matter content)
Soil erosion control (e.g., Pernica lake)
Weed control – suppression of weeds
Moisture retention in the soil (protection of soil against direct sun rays)
Long-term pest control
Easier soil cultivation - suitable for minimum tillage
Beneficial for bees and wild pollinators
Improved aesthetic value of the landscape

Strengths/ advantages/ opportunities in the compiler’s or other key resource person’s view
Non-winter-hardy cover crops improve soil structure, increase organic matter content, increase the number and variety of soil (micro)organisms and enhance nutrient cycling, leading to more fertile and resilient soils. They also help in nutrient retention.
The root systems of cover crops help anchor the soil, reducing erosion caused by wind and water.
Continuous cover with cover crops can suppress weeds, reducing the need for herbicides.
Certain cover crops can break pest and disease cycles, contributing to healthier crops.
Honey producing non-winter-hardy cover crops support pollinators.

6.8 Weaknesses/ disadvantages/ risks of the Technology and ways of overcoming them

Weaknesses/ disadvantages/ risks in the land user’s view	How can they be overcome?
Time- and labor-intensive, requiring significant coordination in terms of timing, weather, and other conditions to meet the deadlines set within the framework of the Common Agricultural Policy – CAP, if the farmer wants to get subsidies for this planting cover crops.	Farmers have greater influence in policy making. Bottom-up approach.
Additional seed cost.	The farmer enrolls in CAP measures to receive a subsidy for this measure.
Initial costs when purchasing equipment, additional investments, and changes in work technology.	Equipment rental, applying for funding grants for equipment, and modifying already existing machinery.
Complexity of management, more demanding planning, and necessary knowledge.	Education
Farm conditions vary, and the effectiveness of cover crops depends on soil type, climate, and local conditions, which can affect growth and overall benefits.	Selecting suitable cover crop mixtures adapted to local soil and climate conditions. Flexible management practices, regular monitoring, technical support, education.
Inappropriate use	Education

Weaknesses/ disadvantages/ risks in the compiler’s or other key resource person’s view	How can they be overcome?
Establishing and terminating cover crops require additional time and labor, which can be a limiting factor for some farmers.	Good planning, collaboration with other farmers, subsidies, and awareness of the long-term benefits of this method encourages the farmer to be more willing to invest effort.
Additional costs for seed purchase and extra labor.	The farmer enrolls in CAP measures to receive a subsidy for this measure.
Potential challenges in soil preparation.	Appropriate equipment, planning, selection of the right plant varieties.
Complexity of crop management and planning.	Education, planning, record keeping.

7.1 Methods/ sources of information

7.2 References to available publications

Title, author, year, ISBN:

Quintarelli, V., Radicetti, E., Allevato, E., Stazi, S. R., Haider, G., Abideen, Z., Bibi, S., Jamal, A., & Mancinelli, R. (2022). Cover Crops for Sustainable Cropping Systems: A Review. Agriculture, 12(12), 2076.

Available from where? Costs?

https://doi.org/10.3390/agriculture12122076

7.3 Links to relevant online information

Title/ description:

Ministry of Agriculture, Forestry and Food. (2024). Unified Application 2024: Guidelines for the implementation of interventions under the Strategic Plan of the Common Agricultural Policy 2023–2027. Ljubljana, Slovenia.

URL:

https://www.kgzs.si/uploads/eiv24/NAVODILA%201/00_VELIKA_NAVODILA_2024_-_CELOTA_-_28_5_24.pdf

Title/ description:

SARE: Cover Crops for Sustainable Crop Rotations

URL:

https://www.sare.org/resources/cover-crops/

Title/ description:

Recommendations for sowing catch crops and winter cover crops for the sustainable use of arable land (Priporočila za setev naknadnih in prezimnih posevkov, za trajnostno rabo njiv)

URL:

https://www.kmetijskizavod-nm.si/uploads/kgz_nm/travni%C5%A1tvo/Priporo%C4%8Dila_za_setev_naknadnih_in_prezimnih_posevkov.pdf