Modern methods for producing turf based on leonardite and Agro.Bio preparations

Modern state and environmental programs in Ukraine emphasize that the fight against water and wind soil erosion should be considered one of the priority tasks in the system of measures taken for the further sustainable development of agricultural production and the conservation of land resources.

Under the influence of precipitation and changing air temperatures, the slopes of hydraulic structures, canal banks, railway beds, and highways are subject to erosion and destruction. Erosion processes at hydraulic structures reduce the strength and reliability of earthen dams and erode the banks, necessitating more frequent cleaning and deepening of canals. In Ukraine's industrial regions, particularly the Dnipropetrovsk region, water and wind erosion affect the slopes of the Orel Canal, irrigation systems, modern highways, and other structures.

The most reliable and accessible means of increasing the stability of slopes is to create a durable turf cover on their surface .

Turf, or sod, is the top layer of soil covered with herbaceous vegetation and densely interwoven with roots and rhizomes. Its roots bind the topsoil, increasing its permeability and reducing thermal conductivity. On steep slopes, the demands on turf are greater: stabilization of the surface is typically achieved by sodding rather than by seeding grass. A difficulty with sodding is the lack of good turf. Sod from natural meadows is typically used for this purpose. However, turf of the required quality is often insufficient.

In the Dnipropetrovsk region, natural meadows with full-fledged turf are virtually nonexistent. Therefore, artificial turf is needed. According to modern specialized research institutions and specialists at Agro.Bio , high-quality artificial turf is produced by growing perennial grasses on leonardite substrates .

Until recently, leonardite deposits in the Dnipropetrovsk region were poorly explored and considered unsuitable for large-scale mining and agricultural use. Soil survey data revealed that the former Orel River bed contained numerous marshy areas. With the construction of the Orel Canal, the groundwater level in this area dropped to 2-2.5 meters, opening up areas rich in leonardite and humified organic matter over an area of ​​approximately 5,000 hectares. Surveys revealed that most of these deposits are highly decomposed.

With nutrient-rich leonardite substrate available near the canals, Ukrainian agronomists began studying the cultivation of turf on the leonardite sections of the Orel Canal.

Methods of obtaining leonardite turf

Obtaining turf by growing perennial cereal grasses on leonardite was solved in two ways:

1. By sowing perennial grasses directly on the leonardite massif.
2. Perennial grasses were sown on a substrate prepared from leonardite with the addition of mineral fertilizers and modern humic stimulants. To address the second aspect, experiments were conducted in specially shaped growing vessels, and leonardite turf was grown on polyethylene film.

The objectives of our research included:

• Identification of promising species of perennial turf-forming grasses taking into account the specifics of the turf;
• Development of effective agricultural methods for their cultivation in order to obtain durable leonardite turf (study of the influence of fertilizers, seed sowing rates, sowing times);
• Study of the growth and development characteristics of various types of perennial grasses in connection with their resistance to unfavorable meteorological conditions;
• Study of the survival rate of turf after its transplantation to the places to be secured.

Conditions and methods of conducting experiments

Vegetation experiments were conducted from 2022 to 2023 at a farm in Dnipro in 0.12 m², 3 cm high pots, ^with four replicates. Leonardite soil near the Orel Canal was used for the experiment. Plants were watered with plain water to a moisture content of 60% of the total water capacity. Field experiments were conducted at the Peremoha agricultural enterprise in Dnipropetrovsk Oblast from 2023 to 2025 on leonardite soils near the Orel Canal. Plot size was 25 m² ^. The experiments were repeated four times. Grasses were grown according to accepted agricultural practices for our region. Grass seeds were sown by hand.

The growth and development of perennial grasses during ontogenesis were studied using generally accepted methods. Projective cover was determined using a standard method. Biomass and shoot formation dynamics were recorded by collecting 1 dm2 sod samples ^at the following times: spring resumption of vegetation, booting, and resumption of autumn growth processes. Sod cover quality was assessed based on grass stand density and shoot density. The weight indicators of the aboveground and belowground parts complemented the sod characteristics. Root volume and sod tensile strength were determined using specialized methods. Data on biomass accumulation and shoot formation were processed statistically. The accuracy of the experiments ranged from 1.3 to 5.0%. The HSR ₀₅ value shows that the established difference between the observed experimental variants is reliable in most cases.

Identification of promising species of perennial turf-forming grasses

The quality of turf depends on its formation process, which in turn is determined by the growth and development characteristics of the turf-forming grasses. When selecting a range of perennial grasses, we considered the grass ecotype, that is, their suitability to a given soil and climate zone, and their tillering pattern.

According to the type of tillering, the most valuable for obtaining a strong turf are low-growing, rhizome-loose-bushy grasses .

In our studies on growing turf on leonardite substrates, we used some of the species recommended for slope stabilization by modern researchers: awnless brome, straight brome, crested wheatgrass, meadow fescue, red fescue, meadow bluegrass, perennial ryegrass, white bentgrass, stolon bentgrass, and wheatgrass without rhizomes. A more detailed ecological study in our experiments was subjected to awnless brome, crested wheatgrass, red fescue, meadow fescue, perennial ryegrass, white bentgrass, meadow bluegrass, as well as grass mixtures: crested wheatgrass 40% + awnless brome 40% + blue-hybrid alfalfa 20%; meadow fescue 33% + crested wheatgrass 33% + awnless brome 33%.

Preliminary experiments were conducted in a greenhouse with 12 species of perennial grasses and two grass mixtures. From these, we selected a mixture of species that we subsequently studied in the field. In the field, perennial grasses were sown in early spring (April 14–20) and autumn (August 20–25). Single seedlings were obtained on April 28 and May 2, and mass seedlings were obtained on May 5–10. Tillering began in early June. In autumn sowings, single seedlings were obtained on September 10–15, and mass seedlings were obtained on September 20–25. Tillering began in late October. Since the grasses were grown without irrigation, during the dry summer period, from late June through September, they acquired a yellow color and entered a state of depression. Growth processes resumed in mid-September.

Table 1. Formation of perennial grass stand in the first year of vegetation

(average data from field experiments for 2024-2025)

The table shows that during the mass emergence period, all species had approximately the same density of 5,500–6,500 plants per square meter ^. From the time of emergence until the resumption of growth in the fall, the number of plants decreased due to unfavorable meteorological conditions during the summer. Crested wheatgrass, red fescue, and a mixture of crested wheatgrass with awnless brome grass and blue-hybrid alfalfa showed a slight decrease in plant density. Meadow fescue, awnless brome grass, and perennial ryegrass were particularly affected by the drought. Crops of white bentgrass and meadow bluegrass were completely destroyed.

The quality of the grass cover in the first years of vegetation is best characterized by the number of shoots of grasses per unit area and their changes during the growing season. Assessing the quality of the turf at the end of the growing season by the number of shoots in crested wheatgrass, red fescue, and grass mixtures, it can be considered good. These same grass species demonstrated the highest projective cover (90-100%), while perennial ryegrass and meadow fescue had a projective cover of 40-45%.

The strength of the turf depends largely on the depth of root penetration and the degree of branching in the upper horizons. By the end of the growing season, the greatest amount of root mass was formed by pure crops of crested wheatgrass and red fescue (1340-1330 g/m2 ⁾ , and somewhat less by meadow fescue, perennial ryegrass, and grass mixtures (1100-1050-1230 g/m2 ⁾ .

Table 2. The effect of different types of perennial grasses on the quality of turf by the end of the first year of life

(average data from field experiments for 2024-2025)

From the same table it is clear that there is a positive correlation between the accumulation of root mass, root volume and turf tensile strength.

In the second year of the grass's life, the same growth and development trends were observed, but by the end of the second year, the number of shoots and root weight per unit area had almost doubled compared to the first year. The tensile strength of the turf also increased accordingly. In 2025, severe weather conditions severely thinned the perennial ryegrass, red fescue, and meadow fescue crops. Awnless bromegrass and crested wheatgrass plants emerged from their free growth stages but failed to produce ears.

Thus, the results of our research showed that, of the studied perennial grasses on leonardites in the Dnipropetrovsk region, in non-irrigated conditions, the highest quality turf is formed by red fescue, crested wheatgrass, meadow fescue, as well as grass mixtures of these species .

The influence of the seeding rate of perennial grass seeds on the formation of turf

The seeding rate plays a crucial role in the formation of high-quality turf. To study this issue, we conducted pot and field trials from 2022 to 2025. Current data shows that high-quality turf is produced with 35-40 plants per 1 dm² ^. Therefore, we used a seeding rate of 40-60-80-100 million viable seeds per hectare.

The results showed that in pure grass crops, the seeding rate affects the root weight, root volume, and root saturation of the soil.

Table 3. Effect of seeding rate of perennial grasses in pure and mixed crops on the growth and accumulation of root mass

(vegetation experiments)

The seeding rate affected the growth and development of the aboveground part of different grass species differently. Plant height generally decreased with increasing seeding rates for crested wheatgrass, meadow fescue, and grass mixtures. The air-dry weight of the aboveground mass of grasses increased in most cases with an increase in the seeding rate from 40 to 60 million seeds per hectare, and remained unchanged or even decreased with further increases in seeding rate (Table 4).

Table 4. The influence of the seeding rate of perennial grasses in pure and mixed crops on the growth and development of the aboveground part

(vegetation experiments)

In field experiments, the same seeding rate during the autumn growing season provided a different number of plants, different total tillering, and different projective cover.

Table 5. Effect of seed sowing rate on the growth and development of perennial grasses in pure and mixed crops in the first year of life

(Field experiments 2024)

With the same seeding rate, the weight of the roots, their volume, and the tensile strength of the turf are not the same for different types of grass (Table 6).

Table 6. Effect of seeding rate of perennial grasses on the quality and strength of turf in the first year of life

(Field experiments 2024)

In the second year of life, the number of plants and shoots per unit area of ​​various grass species decreases significantly, while tillering, root weight, and turf tensile strength increase significantly. The highest turf tensile strength (22.0 kg/dm2 ⁾ was observed in the grass mixture (Table 7).

Table 7. The effect of the seeding rate of perennial grasses in pure and mixed crops on the quality of the turf cover in the boot stage - the 2nd year of life

(field experiments 2025)

The best seeding rate for the formation of strong turf is 80 million seeds per hectare , which corresponds to 180-200 kg/ha.

The influence of Agro.Bio fertilizers and preparations on turf formation

Artificially created embankments and canal slopes are often characterized by soils deficient in essential plant nutrients and weak microbiological activity. Leonardite substrates have high potential fertility but require additional nutrients in a digestible form. The application of mineral fertilizers promotes nutrient mobilization and activates microbiological processes. Furthermore, fertilizers provide a high potential for vegetative regeneration.

To study the effect of fertilizers on turf quality, we conducted vegetation experiments. In the experiments, fertilizers were applied at a rate of 1 liter of 18% ammonia water and 1.2 kg of simple superphosphate per 100 kg of leonardite with 50% moisture content, along with the innovative Totem Agro.Bio product (2 l/ha) . This combination of fertilizers was applied to maximize the activation of leonardite's organic matter and enhance microbiological activity, thereby prolonging the growing season.

The results of the experiments showed that the application of fertilizers and the biostimulant Totem Agro.Bio promoted accelerated growth and development of cereal grasses. For all grass species, the stem height on the fertilized leonardite doubled, the number of shoots increased 2-2.5 times, and the aboveground weight increased 2-3 times compared to the control (Table 8).

Table 8. The effect of fertilizers on the formation of perennial grass stand

(average from vegetation experiments in 2022-2023)

Fertilizers at all seeding rates increased the amount of chlorophyll in leaves (Table 9).

Table 9. Effect of fertilizers and seeding rates on the chlorophyll content in the leaves of cereal grasses

The data obtained can be used independently to grow leonardite-turf "carpets" on polyethylene film. A 1.5 to 3 cm thick leonardite substrate is spread on the film and various grass species are sown. For example, we sown a mixture of red fescue and meadow grass on August 20, 2025, on a film with a leonardite substrate and fertilizer. By mid-October, it had formed a strong turf (10-12 kg/dm² ⁾ that was easily transported.

Leonardite turf survival rate

The final stage of our work is the establishment of leonardite turf on the slopes of hydraulic structures and its use for landscaping the slopes of neighborhoods, new buildings, and some city enterprises. Preliminary survival tests were conducted in a greenhouse at a Dnipro farm. The turf has taken root well.

Based on this, second-year turf grown on a test plot at the Peremoga agricultural enterprise was used to stabilize the slopes of the Frunzenskaya Irrigation System's storage basin in 2024. The turf was cut into 40x40 cm squares. All turf established well, largely due to treatment with Amino Energy Agro.Bio stress reliever (2 l/ha) . After two months, plant roots penetrated the soil to a depth of 11-16 cm, and during the autumn growing season, to a depth of 14-19 cm.

Leonardite turf grown on polyethylene film was used to stabilize the slope in T. G. Shevchenko Park, as well as for decorative purposes at large-scale environmental exhibitions and presentations by agricultural universities.

Conclusions

• The main factor in producing leonardite turf is the development of a dense grass stand and a strong root system. On leonardite substrates in years with normal moisture levels, the most promising species are red fescue, meadow fescue, crested wheatgrass, awnless brome grass, and grass mixtures of these species.
• The strength of the turf depends largely on the seeding rate. The best seeding rate is 80 million viable seeds per hectare (180-200 kg of seed per hectare). High-quality turf of perennial grasses is produced in the second year of their growth.
• The application of pre-sowing mineral fertilizers together with the Totem Agro.Bio stimulator (2 l/ha) when growing grasses on leonardite accelerates the growth and development of plants, increases their decorative properties and ensures the formation of leonardite turf in a shorter period of time.
• Turf grown on a substrate of leonardite and fertilizer on polyethylene film is highly durable, lightweight, and easily transportable. This lawn "carpet" can be achieved in 10-12 weeks.
• When turf grown on leonardites is transferred to slopes, especially with the support of Amino Energy Agro.Bio anti-stress preparations (2 l/ha) , it takes root well and protects the soil from destruction.

Agro.Bio's use of modern biotechnological developments takes phytoremediation and erosion control methods to a fundamentally new level. Using the unique properties of Ukrainian leonardite in combination with Totem and Amino Energy products allows for the rapid formation of a strong turf framework that is resistant to temperature fluctuations and drought. Agro.Bio continues to develop this technology, offering farmers and municipal enterprises effective tools for the ecological restoration of soils.