Ponad połowa użytków rolnych w Polsce jest silnie zakwaszona. Dlaczego zamiast is it worth choosing lime over nitrogen fertilizers? How can agriculture help with this? regenerative?
– In Poland, as much as 64% of agricultural land (9.4 million hectares) requires liming due to severe soil acidification, with 6.7 million hectares having a pH below 5.1, which signals the beginning of devastation – says agronomist Maciej Kobus – a representative of HeavyFinance.
What is the cause of this situation? The blame does not lie solely with the farmers. Most agricultural soils in Poland naturally lower their pH due to natural processes. These are soils that are naturally acidic. Nature tends to move in this direction, but farmers should aim to maintain a pH between 5.5 on light soils and 6.2-6.5 on heavy soils. – Kobus points out that a decrease in soil pH below 5.1 leads to lower fertility, which in turn results in a decline in the yields of major crops.
The “National report on the state of agricultural land in Poland: soil acidification and its regeneration through liming – current state and proposals for systemic solutions” from February 2022 says that in the transitional climate in which Poland finds itself, the land has a natural tendency to acidify. This makes it all the more necessary to take care of improving its quality, raising the pH level, and keeping it at a good level and liming is the best way to do this, experts from the Healthy Soils Coalition point out.
One ton of lime per hectare per year
– Among many farmers, there is a saying – one ton of carbonate lime per hectare per year. That’s how much is needed to maintain the pH at a certain level. If someone applies 4 tons of lime once every 4 years, they won’t raise the pH. In that case, they will only stop the soil acidification process. – Maciej Kobus emphasizes.
Do farmers perform liming regularly? According to the presented results, there are many indications that such actions are lacking. – Most often, this is worse in smaller farms. It is not due to a lack of awareness, but rather the absence of a visible ‘WOW effect’ after liming, like what happens after nitrogen fertilization. Liming is a long-term process. It is spread over time. One treatment is not enough. Bringing the soil to the appropriate pH level takes 6-10 years on heavy soils – Maciej Kobus emphasizes.
Many farmers do not think long-term. Indeed, bringing the soil to the proper pH level often takes several years, but it is an investment that brings tangible benefits, including higher yields, which lead to greater profits for farmers. Farmers who take care of healthy soils make significantly lower investments in purchasing fertilizers, have healthier products, and more satisfied customers,” says Alina Masse from the Healthy Soils Coalition.
Farmers with low soil pH, hoping for quick results, often prefer to invest in nitrogen fertilizers at the expense of lime. However, this is not the best approach. Additionally, funding is still available for liming. Although the “National Program for Environmental Soil Regeneration through Liming,” implemented from 2019, ended in 2023 and offered the most support to the smallest farms, it is not the end of assistance available for this practice. Currently, the eco-scheme “Carbon Farming and Nutrient Management” provides such support. Assistance is available once every four years, and the plots to be limed must have a pH value of no more than 5.5.
Without the appropriate pH, nitrogen won't help but will actually cause harm.
When choosing increased nitrogen fertilization instead of liming, it is important to remember that with an unfavorable pH, the soil’s ability to absorb nutrients is reduced. – If the pH level is around 4, nitrogen is utilized at only 30-40%. The situation only worsens because sulfur and nitrogen fertilizers further acidify the soil. – says the specialist.
– Essentially, the more fertilizer, the higher the expected yield—wheat, for example, requires 27-30 kg of nitrogen per ton of yield, so for a yield of 10 tons, it should be 270-280 kg of N per hectare. However, such yields are not always achievable, and some farmers apply too much fertilizer. In doing so, they unnecessarily increase their costs. – Kobus explains, referring to the concept of Liebig’s barrel, which states that the factor limiting production is the component present in the smallest quantity. – Figuratively speaking, a chain is only as strong as its weakest link. In the case of crop production, this could be water, soil pH, or the availability of other nutrients in the soil. Taking soil samples and understanding the soil are therefore fundamental. And this is not new—this has been taught for over 50 years. – explains the agronomist. – It is best to conduct tests every 2 years, but at least once every 4 years is absolutely essential. This way, we know which fertilizers to use and how they will behave.
Regenerate and earn as much as possible
– Soil regeneration involves restoring its biological, physical, and chemical fertility. The proper pH level is crucial for rebuilding these properties. Regenerated soil will positively impact other environmental resources, such as the atmosphere—by sequestering carbon dioxide, water—by reducing surface runoff, and biodiversity—by creating favorable conditions for the development of soil flora and fauna. – explains Maciej Kobus, transitioning to the increasingly popular term in Poland – regenerative agriculture. – This term is primarily associated with no-till farming, but soil treatment is actually just one of many components. Regenerative agriculture also includes planning based on weather patterns. We analyze long-term data from a specific region, and based on this, it may turn out that increased fertilization will not bring the desired results… All of this is done to maximize farmers’ profits while simultaneously caring for the environment. .
This approach is not unfamiliar to farmers in our country. An example is Wojciech Orliński, who has been running a farm on nearly 300 hectares in the village of Lucim in the Kuyavian-Pomeranian Voivodeship for 44 years. – As a farmer with such experience, I can say that the key to success in agriculture is to love the land we cultivate. To love it and take care of it .
Recently, Orliński joined the carbon programme of HeavyFinance, which aims to generate carbon certificates. The foundation of the initiative is conducting soil tests. – The company has already conducted soil tests on my farm in the spring, primarily checking the carbon level in the soil. For me, organic matter has been very important for a long time, as it obviously affects soil fertility and productivity. – the farmer notes that, thanks to the program, he receives the results of the soil tests conducted by the company for free, and he can also potentially earn additional income from carbon certificates. According to HeavyFinance, on average, farmers can receive 200 PLN per hectare, with the first payments expected to be made next year.
– Practically every farmer nowadays feels the challenges related to the lack of sufficient rainfall. Regenerative agriculture helps the soil better cope with drought – says Eryk Frontczak, head of the carbon program at HeavyFinance. – It is a kind of balancing act between the size of production and the costs incurred. In our carbon program, we take into account not only economic efficiency but also pH, carbon content in the soil, and many other factors. This leads to a reduction in emissions while simultaneously increasing profitability production – emphasizes Frontczak. – Carbon certificates and the additional income farmers will be able to earn from them are the crowning achievement of our efforts, he concludes.
