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Article

A Comparative Plant Growth Study of a Sprayable, Degradable Polyester–Urethane–Urea Mulch and Two Commercial Plastic Mulches

by
Cuyler Borrowman
1,2,
Karen Little
1,
Raju Adhikari
2,*,
Kei Saito
1,
Stuart Gordon
3 and
Antonio F. Patti
1,*
1
School of Chemistry, Monash University, Clayton, VIC 3800, Australia
2
CSIRO Manufacturing, Clayton, VIC 3168, Australia
3
CSIRO Agriculture and Food, Werribee, VIC 3030, Australia
*
Authors to whom correspondence should be addressed.
Agriculture 2025, 15(15), 1581; https://doi.org/10.3390/agriculture15151581
Submission received: 29 November 2024 / Revised: 11 July 2025 / Accepted: 15 July 2025 / Published: 23 July 2025
(This article belongs to the Special Issue New Challenges and Trends in Agri-Environmental Management: Accomplishment of Sustainable Development Goals)
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Abstract

The practice in agriculture of spreading polyethylene (PE) film over the soil surface as mulch is a common, global practice that aids in conserving water, increasing crop yields, suppressing weed growth, and decreasing growing time. However, these films are typically only used for a single growing season, and thus, their use and non-biodegradability come with some serious environmental consequences due to their persistence in the soil and potential for microplastic pollution, particularly when retrieval and disposal options are poor. On the microscale, particles < 5 mm from degraded films have been observed to disrupt soil structure, impede water and nutrient cycling, and affect soil organisms and plant health. On the macroscale, there are obvious and serious environmental consequences associated with the burning of plastic film and its leakage from poorly managed landfills. To maintain the crop productivity afforded by mulching with PE film while avoiding the environmental downsides, the development and use of biodegradable polymer technologies is being explored. Here, the efficacy of a newly developed, water-dispersible, sprayable, and biodegradable polyester–urethane–urea (PEUU)-based polymer was compared with two commercial PE mulches, non-degradable polyethylene (NPE) and OPE (ox-degradable polyethylene), in a greenhouse tomato growth trial. Water savings and the effects on plant growth and soil characteristics were studied. It was found that PEUU provided similar water savings to the commercial PE-based mulches, up to 30–35%, while showing no deleterious effects on plant growth. The results should be taken as preliminary indications that the sprayable, biodegradable PEUU shows promise as a replacement for PE mulch, with further studies under outside field conditions warranted to assess its cost effectiveness in improving crop yields and, importantly, its longer-term impacts on soil and terrestrial fauna.

1. Introduction

Single-use, non-degradable plastic waste is a global problem, and the agricultural sector is a major contributor [1,2]. The conventional practice of spreading polyethylene (PE) mulch film over the soil surface in ridge–furrow cropping systems is beneficial from the crop productivity and water conservation perspectives but detrimental from a sustainability and environmental pollution perspective [3,4,5,6,7,8,9]. In 2011, in China alone, over 1.2 million tons of single-use PE mulch was used to cover nearly 20 million hectares (ha) of cropland [2]. This practice employed worldwide creates a large environmental burden, largely from the deleterious effects of the subsequent microplastic contamination in agricultural fields [10,11,12] but also from incineration and poor waste disposal practices [13,14], and others [15,16] have shown the eco-toxic effects of microplastics on soil and terrestrial fauna, with an associated decrease in crop productivity.
However, it is well known and accepted that mulching with plastic film conserves soil moisture, reduces evaporation losses, suppresses weeds, and, by these effects, significantly improves crop yield [17,18,19]. With United Nations models predicting an increase in food and water insecurity [20,21,22], it is vital that the practice of the cost-effective mulching of crops is not abandoned but rather modified to use sustainable, biodegradable, and environmentally benign technologies.
Biodegradable polymers, e.g., aliphatic polyesters such as polylactide (PLA), poly (ε-caprolactone) (PCL), and poly (3-hydroxyalkanoate) (PHA), are being investigated for application in the form of film-based mulches [23,24,25,26,27,28,29,30] as alternatives to PE as they address the environmental concerns associated with plastic pollution and reduce the long-term costs associated with disposal. These polymers can be hydrolysed under (industrial) compost conditions into CO2 and water, with the rate of degradation depending on their crystalline structure, the degree of UV exposure, the composting temperature, and populations of amenable bacteria. There is also an emerging branch in this field: sprayable, biodegradable polymers, given their simple application and easy customisability [31,32,33,34,35,36,37,38,39,40,41]. By harnessing this technology, the benefits of plastic mulching can be realised without the consequences associated with plastic waste.
A new sprayable, biodegradable polyester–urethane–urea (PEUU) mulch developed by the Commonwealth Scientific and Industrial Research Organization (CSIRO) and applied as an aqueous emulsion has been shown, at loadings greater than 1 kg/m2, to be effective in conserving soil moisture in different soils over a range of environmental conditions and in suppressing weeds [31,42].
This paper presents experimental data obtained under glasshouse conditions showing the effects of PEUU application on soil nutrient availability, plant (crop) growth, and fruit quality. These are compared with data from treatments using commercial PE films: a black polyethylene film and a transparent oxo-degradable polyethylene film. The objective of the study was to investigate the effect of the sprayable PEUU on plant growth, i.e., to understand whether the applied PEUU impeded plant growth and reproduction (fruiting). To ensure the study provided applicable insights, the trial was carried out in pots set in a greenhouse, using soil, tomato seeds, and a fertiliser program sourced from an active, commercial tomato farm in Echuca, Victoria, Australia, from the site of an earlier field trial, and a loamy soil, which is a common soil type prevalent in agricultural areas worldwide.

2. Materials and Methods

2.1. Materials

Soil (a red Vertosol) was collected from a well-tilled, commercial tomato farm in Echuca, Australia (36°09′18.9″ S 144°38′50.6″ E), prior to the growing season up to a depth of approximately 20 cm. Soil from this farm is typical of the clay loam soils cultivated in the central-north and north-western riverine area of Victoria to produce irrigated or dryland grain, fodder, and/or horticultural crops. The soil was air-dried under cover for more than two weeks before being sieved through a 2 mm sieve (US Mesh 10). Representative subsamples of the soil (5–10 g) were analysed for a range of key physicochemical properties (Table 1) by the Environmental Analysis Laboratory at Southern Cross University as per methodologies outlined by Rayment and Lyons [43].
The farmer noted the soil’s inherently low organic matter (1 to 2%), that the soil is subjected to multiple heavy tillage passes before and after tomato crops, and that metham sodium is used in a strip down the centre of the planting bed to stem nematode activity in the crop. Metham (or metam) sodium is a dithiocarbamate soil fumigant with fungicide, nematocide, herbicide, and insecticide activity. Li et al. [44] have shown that metham sodium can significantly impact soil bacterial community diversity.
Tomato seeds were obtained from Kagome®, Echuca, VIC, Australia, and grown to seedlings for three weeks in a commercial seed-raising mix before being transplanted into individual pots containing the homogenised (sieved) Vertosol. The seeds were of the same variety used on the farm from which the soil was obtained.
Mulches used in the treatments included commercial black non-degradable polyethylene (NPE); a transparent, slotted (perforated by repeating slits in the centre of the film), Sunstate Packaging, Australia, oxo-degradable polyethylene (OPE); Eco-One, Australia and the CSIRO sprayable, water-dispersible, biodegradable PEUU [31,42].

2.2. Tomato Growth Trial Conditions and Maintenance

The tomato growth trial was initiated in March 2019 in a temperature-controlled glasshouse at Monash University Clayton, Victoria, Australia. The trials consisted of four treatment groups in total, of which three were plastic mulches (PE, OPE, and PEUU) and one was an unmulched control group (C). Treatments were replicated six times in 24 cm internal diameter, free-draining polypropylene (PP) pots (one plant per pot) set up in a temperature-controlled greenhouse with a mean day–night temperature of 26 °C and 16 °C, respectively (temperature ranged from 25 to 31 °C during the day and from 14 to 18 °C at night). Pots were set up underneath full-spectrum high-intensity discharge (HID) lights set to a 16–8-h day–night cycle, and the illumination level was ramped from 0 to 30 klux during the cycle.
Pots were filled with 8 kg of soil and brought to 50% of the soil’s experimentally determined field capacity by adding 2.1 L of tap water. To mimic the typical farm practice, subsurface drip irrigation, two Falcon® 50 mL centrifuge tubes, with their bases removed, were inserted into the soil on either side of the pot. These were capped at all times, except when watering the tomato plants.
Tomato seedlings were then transplanted from the seed-raising mix into the centre of each pot, one per pot. Finally, mulching treatments were applied to the soil surface by being cut to the appropriate dimensions in the case of the plastic film mulches (PE and OPE) and by being applied as a liquid suspension (20% solids by weight) at a loading of 1 kg m−2 via syringe in the case of the sprayable, biodegradable polyester–urethane–urea (PEUU). The sprayable PEUU cured into a film over the course of 24 h. Figure 1 shows the pots immediately after the set-up was completed.
During the growing period, the plants were watered 3–4 times per week, and after each watering event, the pots were repositioned randomly. Watering was conducted by removing the caps from the buried centrifuge tubes and pouring water directly into the tubes, where it would then run into the soil at a depth of approximately 10 cm. The laid depth of subterranean irrigation tape is dependent on the soil type and crop, typically varying from 10 cm to more than 30 cm. At 10 cm, depending on the soil and upward capillary action, the surface soil can become moist. The amount of water added was determined gravimetrically in the following way: The initial total mass of the pot, plant, soil, and water was known for each pot, and any mass loss was assumed to be due to evaporation. The mass of water lost from each pot between watering events was recorded, to assess the water-saving efficacy of PEUU in comparison to commercial products. Fertiliser was applied once weekly for the first 12 weeks post transplant according to the fertiliser program used at the commercial farm from which the soil and tomato seeds were obtained (fertiliser program is confidential; a typical tomato farm fertiliser program can be found in the Australian Processing Tomato Grower Report [45]). Fertiliser was applied as an aqueous solution to mimic the subsurface fertigation. The plants were grown to maturity and harvested 136 days post transplanting. Fertilisers included urea (analytical grade, Sigma), CaCl2•2H2O (Sigma), anhydrous ZnCl2 (Sigma), commercial Super Phosphate (RICHGRO), Sulphate of Potash (RICHGRO), and Boron (Manutec), Victoria, Australia.
At maturity, fruit was picked and characterised, and the remaining plant mass (roots plus shoots) was weighed first as fresh and then as dry weights after 24 h of oven drying at 105 °C. Residual PEUU was characterised by gel permeation chromatography (GPC), and soil from each pot was analysed for pH, electrical conductivity (EC), nitrate, and ammonium.

2.3. Plant Sampling and Characterisation

The growth of the tomato plant was characterised by measuring the plant height periodically over the first 50 days of the study and counting the number of flowers that formed and then the number of fruits that developed. The mature fruit number and types of visible defects (blossom-end rot and discolourations) on each fruit were recorded, and as previously stated, at maturity, the mass (fresh and dry) of the whole plant excluding the fruit was determined.
The juice of the fruit from each plant was characterised by homogenising whole fruit from each plant using a mortar and pestle and then measuring the pH and sugar content (Brix). Fruit pH was measured using a pH meter (TPS, WP-80), and fruit Brix was measured by dropping a small amount of the filtered juice onto a refractometer (Livingston, BRIXREF113).

2.4. Soil Sampling and Characterisation

After the harvest of the mature plants, the soil was sampled at two depths, 0–2 cm and 2–12 cm. After sampling, the soil was air-dried before being characterised. Soil pH and electrical conductivity (EC) were determined using a 1:5 (m/m) soil–water suspension ratio [46]. In brief, 20 g of soil and 100 g of DI water were agitated for 1 h and then allowed to settle for a further 30 min. The EC of the supernatant water was first measured using an EC meter (Hach, sensION+ EC5), after which the pH of the supernatant water was measured using a pH meter (TPS, WP-80).
Soil nitrate and ammonium were determined using previously described methods [47,48]. In brief, 5 g of soil was agitated in 12.5 mL of 2M KCl for 20 min, then centrifuged at 4200 rpm for 10 min before being analysed colourimetrically. For soil nitrate determination, an aliquot of the KCl supernatant was mixed with a reagent containing VCl3 and Griess reagent (NED and sulphanilamide in water), and colour was allowed to develop overnight at room temperature; measurement was carried out on a multiplate reader at 540 nm (Multiskan™ GO Microplate Spectrophotometer, Thermo Scientific, Victoria, Australia). For soil ammonium determination, an aliquot of the KCl supernatant was added to an aliquot of sodium nitroprusside reagent (including sodium salicylate, sodium citrate, and sodium tartrate), after which an aliquot of alkaline sodium hypochlorite was added. The colour developed for 2 h before being measured on a multiplate reader at 650 nm (Multiskan™ GO Microplate Spectrophotometer, Thermo Scientific). Soil nitrate and soil ammonium quantities were determined using sodium nitrate and ammonium sulphate standards, respectively.

2.5. Polymer Characterisation

Specimens of the residual PEUU film were collected at tomato harvest and then collected again after being allowed to degrade for a further six months in the pots. Specimens were characterised by gel permeation chromatography (GPC) on a Shimadzu system equipped with a CMB-20A 3.50 version controller system, an SIL-20A HT autosampler, an LC-20AT tandem pump system, a DGU-20A degasser unit, a CTO-20AC column oven, an RDI-10A refractive index detector, and 4X Waters Styragel columns (HT2, HT3, HT4, and HT5, each 300 mm × 7.8 mm2, providing an effective molar mass range of 100–4 × 106). Samples were dissolved in dimethylacetamide (DMAc) containing 4.34 g L−1 LiBr, at a concentration of 1–2 mg mL−1. The columns were calibrated with low-dispersity poly (methyl methacrylate) (PMMA) standards ranging from 1500 to 1,500,000 g mol−1. DMAc containing 4.34 g L−1 LiBr was used as an eluent at a 1 mL min−1 flow rate and 80 °C. Number average (Mn) and weight average (Mw) molecular weights were evaluated using Shimadzu LC Solution software 1.24.

2.6. Data Analysis

All data was analysed using Microsoft Excel 2016, IBM SPSS Statistics 25, or a combination of both. Data cleanup (mean calculations, outlier testing, and formatting) was carried out in Excel. To determine statistical significance, one-way ANOVA tests were carried out with Tukey’s Honestly Significant Difference post hoc testing in SPSS. The significance level was set at α < 0.05.

3. Discussion of Results

3.1. Water Conservation Efficacy

Water loss was determined gravimetrically at each watering event. Figure 2 shows the mass of water lost on average from each mulching treatment over the duration of the 136-day study. As expected, the unmulched control pots lost the most water, a total of 35.8 ± 3.4 kg, over the study duration compared to 31.5 ± 2.1 kg, 30.0 ± 1.7 kg, and 28.0 ± 4.3 kg for the PEUU, NPE, and OPE treatments, respectively. There was no significant difference in water loss between the PEUU-mulched and NPE-mulched pots, and the OPE-mulched pots lost the least water. The OPE mulch was slotted, so cooler soil temperatures may have slowed down evaporation from the soil surface and reduced the rate of water movement through the plant, and this finding was unexpected. The OPE plants also initially grew slower (Figure 2), which possibly was caused by cooler soil temperature associated with non-pigmented mulch, which in turn may have reflected heat, causing the soil to remain cooler, thus slowing tomato seed germination and the seedling growth rate. The reflective cooling also perhaps contributed to the reduced water loss measured for the OPE pots. Indeed, this effect is well known in horticulture wherein reflective mulches are used to reduce the soil temperature and enhance the plant microclimate for crop yield and quality benefits [49,50].

3.2. Soil Analysis

Soil samples from each pot were analysed at two depths (0–2 cm and 2–10 cm) for pH, electrical conductivity (EC), nitrate, and ammonium (Figure 3). These are typically measured characteristics to understand soil health. Quantifying the soil nitrate and ammonium was of particular interest because the PEUU material contained N (in both the repeating carbamate and urea functional groups), and it would have been interesting if that N ended up in the soil in an inorganic form, easily accessible to plants.
There was no change in the soil salinity (as measured by EC) in any of the mulching treatments compared to the salinity of the initial soil. The soil pH rose significantly for all treatment groups, including the control, the initial soil sampled at the two depths, and the soil subjected to the same watering/fertiliser treatments over the growth period. The likely cause of this pH increase was the fertiliser program, which was slightly alkaline (pH > 8) due to one highly alkaline component (pH > 11 when in solution). No differences based on sampling depth were observed. Both soil nitrate and soil ammonium decreased significantly from the initial conditions in all treatments, which was expected, as the tomato plants take up and use both chemical forms of nitrogen. If PEUU did act as a source of inorganic N, the analysis here did not reveal any differences.
Further study under a simpler system, e.g., using a grow medium rather than a soil, would be needed to determine whether inorganic N is released from PEUU or if some inorganic N is released and rapidly assimilated by any plants present. Across the mulching treatments, higher levels of ammonium and nitrate were observed in the soil sampled nearest the surface. This finding is intuitive, as the root density is low at the soil surface (less opportunity for inorganic N to be taken up by the plants), and due to the watering method used (subsurface), there would be little opportunity for these chemicals to leach down the soil profile as they would do with aboveground irrigation methods. This trend was common in all treatment types, although none of the differences between treatments were statistically significant. From a soil physicochemical perspective, the PEUU mulch performed similarly to the conventional, commercially available plastic mulches.

3.3. Plant Growth Analysis

The growth of the tomato plants was monitored by measuring their height periodically over the first 50 days of the trial (Figure 4) and by measuring their wet and dry mass at harvest. Over the first 50 days, the plants mulched with the sprayable PEUU or NPE showed increased growth over those that were not mulched or mulched with OPE; however, these differences were not statistically significant.
In terms of the total plant mass, there was little variation in the wet or dry mass between treatment groups. Interestingly, the plants grown in unmulched conditions had the largest average wet mass, but this was not statistically significant, and after oven drying, the difference in masses between treatment groups was negligible. This data provides some preliminary evidence that the sprayable PEUU does not create any adverse impacts on plant growth (Figure 5).
Fruit Brix, fruit pH, and fruit defects were measured because these are important parameters for both tomato growers and tomato processors (Figure 6). There were no statistically significant differences in any measured fruit characteristic between treatment groups, which contradicts much of the literature that shows that plastic mulching applied in field settings increases crop yield, e.g., as per [3,4]. These findings reflect a limitation of this study and greenhouse pot trials in general, which offer a controlled environment with regulated temperature, humidity, and light in the study of plant–soil feedback treatments compared to the much more complex natural field conditions. Perhaps using larger pots, a larger soil volume, soil mixing, adjusting the temperature and irrigation strategies to reflect field conditions, adjusting the light intensity and duration to mimic natural sunlight, or increasing the replication number would help mimic field conditions, reveal statistically significant trends, and allow for increased fruit growth. The results do, however, provide further preliminary evidence that the application of the sprayable PEUU does not cause large, detrimental effects to plant growth, although further study is necessary to determine if there truly are no adverse effects.
The large number of defects per fruit (ranging from 0.4 to 0.65 defects per fruit) is noteworthy. The preponderance of fruit defects was associated with blossom-end rot (BER), which is caused in part by a calcium deficiency [51], although the influence of favourable or unfavourable growing conditions on the development of BER is still poorly understood [52]. Given that the growth conditions used in this study (soil, tomato cultivar, fertiliser program) were identical to those used at an active tomato farm, the incidence of BER also indicates that a large-scale field trial is necessary to provide optimal growing conditions for the tomatoes.
Tracking the number of flowers per tomato plant over time is another way to gain an understanding of how different treatments affect plant health. Figure 7 displays the average number of flowers per plant per treatment group from Day 43 through to harvest. Each mulch treatment significantly increased the number of flowers per plant compared to the bare control, with the largest increase associated with the sprayable-PEUU-mulched plants. Both the OPE- and NPE-mulched plants were statistically higher than the control at the α < 0.10 level.

3.4. Polymer Degradation

PEUU degraded extensively over the course of the growing period and a further six months, as measured by GPC (Figure 8).
The large error in molecular weight changes observed at harvest (orange bars, Figure 8) is due to some film applications degrading nearly completely (i.e., Mw < 1500 Da) and some films remaining more or less intact although still degraded significantly (Mw between 30 and 90 kDa). After a further 6 months of on-soil degradation, only three pots had any residual PEUU that could be collected and characterised by GPC. This data helps demonstrate that PEUU is effective at conserving soil moisture despite degrading extensively whilst being used.

4. Conclusions

The effects of two commercial plastic mulches and a novel, sprayable, biodegradable polyester–urethane–urea (PEUU) mulch on certain soil physicochemical properties, water conservation, and tomato plant growth were investigated. Pot trials offered a valuable, controlled environment for preliminary research, allowing us to test a wide range of variables and gather data on PEUU for future complex field trials.
Enhanced water savings were observed in plants treated with all mulches, with no differences in the water savings between mulching treatments. PEUU did not have any negative impacts on plant growth measurements nor on any of the measured fruit characteristics while degrading significantly over the course of the tomato plant growth trial period.
The limitations of pot trials are evident in the data presented here. There was no enhanced crop yield for plants grown in the mulched soil, which reflects the stability of the environmental conditions applied in these trials, albeit there was a higher incidence of fruit defects in all treatment groups. However, plants that were mulched formed more flowers, which under more optimised conditions would have been associated with a higher fruit yield.
This study demonstrated that sprayable, biodegradable polymers performed similarly to conventional non-degradable plastic mulches without adverse effects on the soil or plant health and serves as a foundation for further study. This work should be followed up with multiple-year field trials conducted under commercial growth conditions to validate the inconclusive findings on crop yield so as to confirm the PEUU technology’s performance under real field conditions.

Author Contributions

Conceptualisation, C.B., R.A., A.F.P. and K.S. methodology, R.A., A.F.P., C.B. and K.L. investigation, C.B.; writing—original draft, C.B.; writing—review and editing, R.A., K.S. and S.G.; funding acquisition, C.B. All authors have read and agreed to the published version of the manuscript.

Funding

This work was supported by a Monash Graduate Scholarship and a Monash International Postgraduate Research Scholarship. It was also supported by funding from the Commonwealth Scientific and Industrial Research Organisation. A.F.P. is the recipient of an Australian Research Council Industrial Transformation Training Centre Award (Green Chemistry in Manufacturing, project number IC190100034) funded by the Australian Government.

Institutional Review Board Statement

Not applicable.

Data Availability Statement

The datasets generated for this study are available upon request from the corresponding author.

Conflicts of Interest

The authors declare no conflicts of interest.

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Agriculture 15 01581 g001
Figure 1. The final tomato pot set-up with mulching treatments applied: PEUU—polyester–urethane–urea; NPE—non-degradable polyethylene; and OPE—oxo-degradable polyethylene.
Figure 1. The final tomato pot set-up with mulching treatments applied: PEUU—polyester–urethane–urea; NPE—non-degradable polyethylene; and OPE—oxo-degradable polyethylene.
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Figure 2. Water loss from the different mulching treatments during the trial. Error bars represent ± one standard deviation.
Figure 2. Water loss from the different mulching treatments during the trial. Error bars represent ± one standard deviation.
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Figure 3. Soil physicochemical properties. Depth 1 was sampled from the top 0–2 cm of soil, and Depth 2 was sampled from the following 2–10 cm of soil. Data represents mean values (n = 6) ± one standard deviation.
Figure 3. Soil physicochemical properties. Depth 1 was sampled from the top 0–2 cm of soil, and Depth 2 was sampled from the following 2–10 cm of soil. Data represents mean values (n = 6) ± one standard deviation.
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Figure 4. Time series of plant height. Error bars are ± one standard deviation.
Figure 4. Time series of plant height. Error bars are ± one standard deviation.
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Figure 5. Wet and dry tomato plant mass. Error bars are ± one standard deviation.
Figure 5. Wet and dry tomato plant mass. Error bars are ± one standard deviation.
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Figure 6. Fruit characteristics. Data displayed are means ± one standard deviation.
Figure 6. Fruit characteristics. Data displayed are means ± one standard deviation.
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Figure 7. Flower number per tomato plant. Error bars are ± one standard deviation.
Figure 7. Flower number per tomato plant. Error bars are ± one standard deviation.
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Figure 8. Weight average (Mw) and number average (Mn) molecular weight changes in the applied PEUU over the course of the study. Error bars are ± one standard deviation.
Figure 8. Weight average (Mw) and number average (Mn) molecular weight changes in the applied PEUU over the course of the study. Error bars are ± one standard deviation.
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Table 1. Measured soil physicochemical properties.
Table 1. Measured soil physicochemical properties.
CharacteristicVertosol
Ca2+, mg/kg1675
Mg2+, mg/kg524
Na+, mg/kg140
K+, mg/kg58
P(Colwell), mg/kg65
NO3−, mg/kg26.1
NH4, mg/kg3.7
Electrical Conductivity, dS/m0.17
Total C, %1.12
Total N, %0.12
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Borrowman, C.; Little, K.; Adhikari, R.; Saito, K.; Gordon, S.; Patti, A.F. A Comparative Plant Growth Study of a Sprayable, Degradable Polyester–Urethane–Urea Mulch and Two Commercial Plastic Mulches. Agriculture 2025, 15, 1581. https://doi.org/10.3390/agriculture15151581

AMA Style

Borrowman C, Little K, Adhikari R, Saito K, Gordon S, Patti AF. A Comparative Plant Growth Study of a Sprayable, Degradable Polyester–Urethane–Urea Mulch and Two Commercial Plastic Mulches. Agriculture. 2025; 15(15):1581. https://doi.org/10.3390/agriculture15151581

Chicago/Turabian Style

Borrowman, Cuyler, Karen Little, Raju Adhikari, Kei Saito, Stuart Gordon, and Antonio F. Patti. 2025. "A Comparative Plant Growth Study of a Sprayable, Degradable Polyester–Urethane–Urea Mulch and Two Commercial Plastic Mulches" Agriculture 15, no. 15: 1581. https://doi.org/10.3390/agriculture15151581

APA Style

Borrowman, C., Little, K., Adhikari, R., Saito, K., Gordon, S., & Patti, A. F. (2025). A Comparative Plant Growth Study of a Sprayable, Degradable Polyester–Urethane–Urea Mulch and Two Commercial Plastic Mulches. Agriculture, 15(15), 1581. https://doi.org/10.3390/agriculture15151581

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