There are industry-wide concerns regarding sustainability and commercial availability of peat use in horticulture. Providing growers with domestic options can offer flexibility in substrate management decisions and reduce reliance on peat. The objective of this study was to measure the physiochemical properties of two organic domestic agricultural biomass as potential peat reducers. Three substrate components, including (1) palm fiber, (2) redwood bark, and (3) coconut coir, and three substrate composites, including (1) a commercially available peat:perlite mix (Peat-Lite), (2) a 50:50 Peat-Lite:palm fibers mix, and (3) a 70:30 redwood bark:commercially available coconut coir substrate were measured for their chemical, physical, or hydraulic properties. The results showed that both palm fibers and redwood bark components contained low-nitrogen drawdown indices (P < 0.001). Palm fiber contained the greatest sodium levels across the substrate components (P < 0.001). Palm fibers as a standalone component contained the greatest air space (AS; 0.50 cm(3).cm(-3)) and the lowest container capacity values (CC; 0.28 cm(3).cm(-3)) when compared with the other components (P < 0.001). When palm fibers were amended to Peat-Lite, the amended mix had reduced CC when compared with 100% Peat-Lite (P < 0.001). Redwood bark:coconut coir composites contained similar CC and AS values to commercial Peat-Lite. Peat-Lite composites contained the greatest volume of easily available water (0.27 cm(3).cm(-3)) when compared with a Peat-Lite:palm fiber (0.17 cm(3).cm(-3)) and redwood bark:coconut coir mix (0.20 cm(3).cm(-3)). Peat-Lite:palm fiber mixes had the greatest pore uniformity when compared with other composites (P < 0.001), which resulted in a more gradual loss of volumetric water content with decreasing water potentials. However, the Peat-Lite:palm fiber mix had the most rapid moisture loss in moisture redistribution models within a 24-h period. These results provide baseline information regarding the physiochemical and hydraulic properties of two domestically sourced materials: palm fiber and redwood bark. More research is needed to qualify their potential use as a substrate component in containerized horticulture production.

Soilless substrate stratification entails layering two unique substrates with distinctive physiochemical properties atop each other to improve nursery and greenhouse production sustainability. Most stratified research to-date has explored a 50:50 (v/v) or equal top and bottom stratified depth layer ratio. To increase flexibility in stratified substrate and support industry adoption, more research is needed if the stratified depth layer influences plant growth and yield. Thus, the objective of this study was to investigate different stratified depth layers using pine bark substrates when growing a popular woody nursery shrub (Knockout Double Red; Rosa ‘Radtko’), wherein screened fine (≤6.3 mm) pine bark was in the top strata at 6, 12, or 18 cm of depth in a 24-cm-tall container, while the remaining bottom strata contained a respective 18-, 12-, or 6-cm base of screened coarse (6.3 to 12.7 mm) pine bark. A nonstratified pine bark was included as control. This study examined different fertility application rates, top-dressing containers with a low, medium, or high application rate of controlled-release fertilizer. The results showed that the stratification depth layer (P = 0.067) or fertility program> (P = 0.609) did not negatively affect plant growth, where plants grown in stratified systems across fertilizer treatments grew similarly to a conventionally grown plant. Fertilizer application rate (P < 0.001) had a stronger impact on root zone fertilizer salt release than stratification depth layer (P > 0.395). Increasing fertilizer rate increased nitrogen (P < 0.001) and phosphorus (P < 0.001) tissue content, while stratification depth had no influence. In all, this study demonstrated that stratification practices can be used without injury to plant development. Moreover, understanding that depth layer did not negatively affect plant growth increases industry flexibility among those who are interested in adopting stratification management techniques.

Soilless substrate characterization often occurs with fallow substrates, which excludes information about how roots influence substrate properties. This study had two primary objectives: (1) investigate how the presence of root systems alters storage and hydraulic properties of a Sphagnum peat substrate; and (2) assess if data collected can be used in computational infiltration models to infer how root presence changes moisture redistribution. Helianthus annus ’Lemon Queen’ seeds were sown into 347.5 cm3 and 250.0 cm3 cores filled with peat moss. Three treatments were applied: (1) fallow, prior to production conditions; (2) fallow, after 42 d of production conditions; and (3) rooted, after 42 d of plant growth. Storage properties were assessed along with relationships between volumetric water content (θ) and matric potential (Ψ). Afterward, data was used in HYDRUS 1-D to model moisture distribution after maximum water storage conditions. The results showed that rooted substrates proportionally increased water-filled pores (+5%) and decreased air-filled pores (-7%), reduced overall substrate solids by 60%, and occluded 6-10% of the container volume. Rooted systems contained greater θ with declining Ψ than fallow substrates, accompanied by shifts from macropores (i.e., pores with effective diameters >416 µm) to mesopores (i.e., pores between 10 and 416 µm). Moisture redistribution models simulated a reduced moisture differential from the top-to-bottom of the profile after 24 h comparing pre-production fallow (67%) to rooted substrates (26%). These results highlight that root presence alters substrate properties, such that characterization done on fallow media may not adequately reflect actual growing conditions.

Biochar, the product of pyrolyzed organic materials, has environmental benefits of sequestering carbon while stabilizing materials for use in agricultural settings. However, the feedstock used can influence the final biochar product characteristics. This research investigated the impact that biochar derived from bagasse has on an ornamental crop as a soilless substrate component to identify potential uses for sugarcane bagasse, which is the fibrous remains of the plant after sugar extraction. Peat-based commercial substrate was amended with bagasse biochar at 0%, 15%, or 30% (by volume) and used to grow marigold (Tagetes patula 'Janie Gold') plants for 6 weeks under low (100 ppm N) and high (300 ppm N) fertigation regimes. The results indicated that there were no deleterious effects of biochar incorporation on plant growth and suggested that there may be added nutrient retention from fertigation in substrates amended with biochar. The biochar incorporation ratio had less of an effect on foliar concentration than fertility management; in almost every case, greater fertility concentrations resulted in more concentrated foliar nutrition. Plants grown in 30% amended biochar substrates had greater foliar potassium tions increased nutrient retention and extended release when compared with conventional peat-based substrates. Increasing biochar rates decreased container capacity 0.0001). This study suggests that biochar derived from sugarcane bagasse can be incorporated in a commercial peat-based substrate to improve fertilizer efficiency and reduce peat use without negative effects on plant growth.

Considerable research has investigated solutions for alternative substrates in reducing horticulture peat applications. Among many options, soilless substrate stratification has been shown to reduce peat inputs by upwards of 50%, and coconut coir and wood fiber are two popular alternatives to peat in many soilless substrates. Most stratified studies have used a pine bark–based substrata; however, scant research has explored substrata variations to promote more flexibility in stratified substrate management decisions. Therefore, the objective of our study was to explore different variations of the top-strata and substrata materials to identify the potential of reduced-peat and no-peat production of greenhouse-grown petunias. A commercial peatlite or coirlite (7:3 blend of peat/coir:perlite by volume) was layered over pine bark or wood fiber (HydraFiber) at a 50/50-by-volume ratio, as well as an unstratified peatlite or coirlite control. Results show that a petunia plant can be produced successfully with equal quality growth using 50% less peat-based media when pine bark or wood fiber is layered below. Moreover, greenhouse petunias can still be grown to salable and marketable quality (with slightly less shoot, root, and flower development) using systems with 100% peat elimination in coir-based unstratified and stratified (coirlite layered over pine bark or wood fiber) profiles. This work provides more options for growers seeking flexible solutions.

Stratified substrate systems (i.e., layering substrates of differing physiochemical properties within a container) can increase crop growth and quality by improving the profile hydraulic properties; however, no research has examined if these systems enhance gas supply to the rootzone. In this study, we used a one-chamber gas diffusion apparatus to understand how peat-based stratified systems (7:3 by vol. peat:perlite layered over unscreened bark; 1:1 depth layer ratio by vol.) influenced gas exchange when compared to a non-stratified control (100% of a container filled with 7:3 by vol. peat:perlite). We also examined if relative gas diffusivity (D-s/D-0) was modified for different rooting levels (0, 14, and 28 days of growth of a Helianthus annus Lemon Queen crop) and relative wetness of maximum water storage (<10%, similar to 50%, and similar to 75% of container capacity values). Crops grown in the stratified system generally exhibited more root growth compared to those grown in non-stratified systems, including longer roots and greater surface area and volume. The linear increase in rooting measured through time within treatments had negligible effects on D-s/D-0; however, D-s/D-0 varied with relative wetness for both substrate profiles. When moisture was present, stratified systems supplied the rhizosphere with oxygen faster than non-stratified systems. Stratified systems can (1) improve rootzone environments through reduced waterlogging, (2) better resupply oxygen, and (3) decrease peat inputs by nearly 50%.

Production of young plants from cuttings and seed relies heavily on peat and frequent, but light, irrigation. Interest in reducing peat usage as well as a propensity for short container heights to inhibit drainage have led to the exploration of alternative techniques to improve substrate airspace in young plant production. Substrate stratification has been shown to be effective for reducing excessive moisture content and improving root growth in the lower strata of larger containers. This research evaluated the effects of substrate stratification in 5.1-cm tall, 37-cm3 cell plug trays using two plant propagation substrates: a bark-based vegetative cutting substrate (16% peat) and a peat-based seed germination substrate (65% peat). Each substrate was stratified by layering over either a commercially available wood fiber or horticultural grade perlite and was compared with an unstratified control. Substrate physical properties were measured on unplanted substrate treatments. Cuttings of two common bedding plants [coleus (Solenostemon scutellarioides ‘Salsa Verde’) and evolvulus (Evolvulus glomeratus ‘Blue Daze’)] were grown in the vegetative bark-based substrate treatments, and seeds of three common seed-started taxa [basil (Ocimum basilicum ‘Thai Towers’), hibiscus (Hibiscus moscheutos ‘Luna Pink Swirl’), and zinnia (Zinnia elegans ‘Zesty Purple’)] were grown in the seed peat-based substrate treatments. Finished plants were assessed for plug integrity and various growth parameters. Stratification with perlite increased airspace in the vegetative substrate only, not in the seed substrate. Stratification with wood fiber resulted in reduced airspace and increased container capacity in both substrate types. Stratification with perlite decreased plug integrity compared with nonstratified treatments, whereas wood fiber stratification resulted in similar or improved plug integrity, even in treatments in which root growth was reduced. Dry root biomass was greatest in both nonstratified substrates, with perlite stratification generally associated with the lowest root biomass. Perlite stratification was also associated with the lowest total root length and total root surface area, whereas wood fiber stratification resulted in values equivalent or greater than nonstratified treatments. Despite decreases associated with perlite stratification, however, both perlite- and wood fiber–stratified treatments produced quality plugs that established successfully post-transplant. The results demonstrate that using stratification in young plant production may provide growers with an opportunity to reduce peat consumption in propagation operations.

Greenhouse horticulture relies on manual labor for plug transplanting, which is subject to variability in substrate packing density. Little research exists on the effect variable substrate packing density has root morphological development. Petunia hybrid ‘Supertunia Honey’ plugs were grown in peat-based substrates packed at four densities (0.08, 0.10, 0.12, and 0.14 g·cm −3 ). The results indicated that root development was improved with moderately increased substrate density.

Containerized soilless substrates are highly porous to ensure adequate air storage to overcome the “container” effect- the lower part of the container nears saturation which can decrease root health and growth. Substrate porosity is dynamic, evolving over time. As roots fill pores, substrate decomposition and in-situ particle movement change the physical structure, shifting its storage properties and performance. Research is sparse in understanding how developing roots change their morphology throughout production (temporally) and while growing throughout the three-dimensional substrate matrix (spatially). Thus, it would be beneficial to understand how root development impacts container moisture characteristics. This study aimed to quantify root morphological development and water storage (θ) spatiotemporally in conventional or engineered soilless substrate systems. Helianthus annus ‘Rio Carnival’ was grown in 30.5 cm tall PVC columns in a conventional (non-stratified; 100

Containerized plant systems using soilless substrates are increasingly vital to global food and horticultural production, offering efficient resource use and expanded crop production in areas where native soils are not suitable. However, open-air production of containerized plants introduces risks for extreme root zone temperatures (RZTs) that impair root function, reduce growth and increase crop loss. While passive mitigation strategies exist, growers often rely on irrigation to cool substrates during high-temperature events. Without reliable real-time monitoring or predictive tools, RZT management remains sub-optimal, ineffective and wasteful. To address this problem we evaluated the potential for predicting substrate temperature using accessible environmental observations and low-complexity modeling approaches. Environmental conditions and substrate temperatures were monitored from June to October 2024 at experimental sites in Tennessee and Ohio. Each site included trials comparing two ground cover types commonly found in open-air crop production, limestone gravel and black landscape fabric. Despite significant differences in cover temperature, only minor differences in substrate temperatures were observed. Ambient air temperature, downwelling shortwave radiation and vapor pressure deficit all demonstrated strong correlations with substrate temperature, with maximum correlations occurring between 2 and 5 hours prior to the substrate temperature observation. These strong lagged correlations motivated the development of relatively simple (one and two predictor) models of substrate temperature using both machine learning (shallow neural networks) and linear statistical models. Models incorporating air temperature and shortwave radiation achieved strong predictive performance for substrate temperatures (R2 = 0.84–0.93) with lead times up to five hours, demonstrating the utility of models developed using widely available weather observations.

As peat (P) demand increases throughout the horticultural industry, alternative fibers must be evaluated. Sugarcane bagasse (B), wood fiber (W), and coconut coir (C) have received interest as domestically available alternatives to P, with demonstrated success in producing greenhouse crops. However, there is limited research comparing these materials to peat. This research evaluated the substrate properties and productivity of Petunia Supertunia Mini Vista ‘Indigo’ in pine bark substrates amended with C, W, B, or P and fertigated weekly at 100, 200, or 300 parts per million (ppm) nitrogen (N) to account for possible N immobilization. The container capacity was lowest and air-filled porosity was highest in W and B substrates. Substrate pH increased in W and B substrates, and C substrates were fertigated at 100 ppm N. Increasing the N rate increased the growth index in all substrates, especially B and W substrates later in the production period. Higher fertilization increased shoot mass, chlorophyll content, and blooms across all substrates, demonstrating that fertilizer supplementation may offset possible N immobilization. While plant growth and quality parameters were greatest in the P blend, increasing N applications produced similar-quality plants using alternative substrates, demonstrating that modifying fertilizer management practices can make alternative fibers a viable horticultural substrate.

Floriculture crop production heavily relies on the use of peat-based substrates to quickly mass produce containerized crops. The sustainability of using peat moss has been an increasing concern for both horticultural stakeholders and the community. The concept of stratifying soilless substrates (i.e., vertically layering unique substrates atop of each other within the container) has been shown to reduce peat moss applications by upwards of 50 %. Although, most stratified substrate research has only studied an equal partition in which the substrate is evenly split into two layers. This necessitates further studying modification of the limits and optima for the depth of each layer. This study evaluated adjusting this stratified depth layer for possible further benefits, such as reduced water and peat moss applications. Lucky Star Dark Red Pentas lanceolata ‘PAS1231189’ was grown in one of four substrate treatments, including a (1) non-stratified 100 % peat and perlite blend (peat-lite), (2) 13.4 cm peat-lite placed above 4.4 cm pine bark (PB) horizon with the container consisting of 75 % (by vol.) peat-lite and 25 % (by vol.) PB; (3) 8.9 cm peat-lite placed above 8.9 cm PB layer with the container consisting of 50 % (by vol.) peatlite and 50 % (by vol.) PB; (4) 4.5 cm peat-lite placed above 13.3 cm PB with the container consisting of 25 % (by vol.) peat-lite and 75 % (by vol.) pine bark. Crops were placed on irrigation-actuated lysimetry systems to maintain substrate volumetric water contents between 0.20 and 0.30 cm3 cm−3. This study identified successful production of pentas in stratified profiles when the depth layer is ≥ 50 % peatlite by vol., with equal growth to pentas grown traditionally (i.e., 100 % peat-lite; non-stratified). Crops grown in a 25 % peat-lite : 75 % PB depth layer experienced significantly reduced growth with regards to growth index, quality, and dry biomass. Moreover, crops grown in the 25 % peat-lite by vol. also experienced faster peak inflorescence with a subsequent continuous decline in flower development due to water stress; whereas, plants grown in ≥ 50 % peatlite by vol. continued to develop blooms throughout the study. This study demonstrates that a popular floriculture crop can be grown by stratifying expensive floriculture media above inexpensive PB with little to no differences in growth if the stratified peat layer is equal or greater than 50 % the container vol.

To support growth, short-cycle horticultural crops require readily available nutrients. However, this often leads to nutrient leaching. Implementing best management practices in production decisions like incorporating fertilizer retaining amendments to substrates or modifying fertilization programs can mitigate nutrient losses to the environment and associated costs. This study examined using an activated aluminum (AA) material as a substrate amendment to retain phosphorus (P) within containers while also assessing methods to reduce P fertilization in Tagetes production over a six-week production cycle. A commercial peat moss substrate (PL) pre-loaded with nutrients was amended with AA, enabling comparisons between substrates with and without AA. Enhanced fertilizer practices involved supplementing the initial nutrients by applying a weekly fertigation solution including nitrogen and potassium over the six weeks, but P for either 0, 2, 4, or 6 weeks. The incorporation of AA significantly reduced P leaching losses by 89.5–97.7%, compared to the PL substrates receiving P the entire six weeks. Regardless of substrate or fertilizer management, all Tagetes had equivalent sizes (growth index) and aboveground biomass. The results indicate that amending substrates with AA and/or reducing additional P inputs are effective strategies to minimize P leaching without compromising Tagetes quality.

The nursery industry produces and sells plants for landscape and environmental purposes and represents a major sector within the US agricultural industry. In recent years, the nursery industry has undergone rapid growth as a result of various factors, including increased demand from housing development and pandemic-fueled interest in home horticulture. As with any industry, the nursery industry must adapt to changes in societal trends to sustain growth. In the wake of unprecedented societal and supply chain issues stemming from the global coronavirus disease 2019 pandemic, the American Society for Horticultural Science Nursery Crops Professional Interest Group gathered experts in various disciplines to provide their opinions and insights into the future of the nursery industry, focusing specifically on the changes and challenges the nursery industry will face in the coming decade. Nursery crop specialists spanning the United States identified three primary areas that will steer the future momentum of the nursery industry: consumer trends, natural resources, and labor. Six experts were selected to represent these areas in a workshop held Jul 2022 at the American Society for Horticultural Science Annual Conference in Chicago, IL, USA. This article was developed to disseminate to the greater scientific community the discussions held and insight shared during that workshop.

Soilless substrate stratification is increasing in popularity in the greenhouse and nursery industry globally. The concept of stratifying substrates entails stacking two substrates with different physiochemical properties to augment vertical moisture balances and redistribution for quicker establishment, greater root growth, and quicker time to market. Stratified substrate research to date has estimated or assumed that the static physical properties of a stratified system as the mean of the individual strata components. No research to date has verified or rejected this assumption using a stratified column. The research herein measured the static physical properties of 1) peatlite (85% peat: 15% perlite), 2) unprocessed <12.7 mm aged bark, 3) fine bark particles (≤6.3 mm), and 4) coarse bark particles (≥6.3 mm). Moreover, these physical properties were measured via 1) using the standard promoter analysis (7.6 cm core), 2) extending the core height by stacking two standard porometer cores (15.2 cm height) of the same strata component atop each other (to identify how water storage and air-filled porosity changes), and 3) stratifying either peatlite over unprocessed bark or fine bark over coarse bark. The results showed that extending the height of the porometer increased drainage and decreased water storage across conventional and stratified systems alike, illustrating the benefit of using cores equivalent to container height when making cultural decisions to manage water efficiently. When stratifying substrates, the system as a whole stores less water and has more air-filled porosity than nonstratified composite profiles (100% peatlite; 100% unprocessed bark) due to gravitational forces draining the higher portion of the container. Assumptions regarding the static physical properties of a stratified system can be made with the standard or extended porometer core for coarse-textured bark substrates used generally in the nursery industry with reasonable accuracy (<5% difference), meaning that nursery growers interested in stratifying their substrates can assess their stratified static physical properties using standard measurements. However, assumptions cannot accurately be assessed for finer peat-based stratified profiles used in greenhouse production and may require further refinement for estimations. The broader implications of this research highlight the storage capacities of a stratified substrate system, which may influence growers’ decisions in application and irrigation management.

The specialty crop industry requires copious amounts of water to meet production needs; however, current substrates are highly porous to mitigate risks and are subsequently inefficient with regard to water use. Therefore, more sustainable soilless substrates are needed to ensure the future success/profitability of the horticultural industry, especially as finite fresh water sources become limiting. Substrate stratification (i.e., vertically layering unique substrates atop one another) provides opportunities to augment an existing system by maintaining substrate porosity, while strategically redistributing the air- and water-filled pores, retaining more water when applied, and controlling vertical water distribution. The aim of this research was to further understand the complex stratified systems of hydraulics. Herein, the hydraulic properties of individual substrate components were measured and modeled using HYDRUS 1 d. Furthermore, matric tensions and volumetric water content (VWC) were measured continuously under two different irrigation schedules (single [1x] and cyclic applications [3x]) for 15 days with a fully established Dianthus barbatus "Amazon Neon Purple" crop. The results showed that screened bark particles have more pore homogeneity assessed by steep declines in VWC with small changes in water potential. Moreover, HYDRUS 1 d modeling demonstrated that stratified substrates have more uniform hydraulic gradients (difference in moisture content from the top to the bottom of the substrate profile; 21%) present in the container profile when compared to non-stratified systems (45%). Non-stratified upper layers experienced greater diurnal tension fluctuations under single irrigation than in cyclic applications. Stratifying substrates resulted in a significant reduction in these fluctuations in the top layer when compared to non-stratified systems. Additionally, when both substrate (stratifying) and irrigation (cyclic) management strategies are implemented, tension fluctuations can be even further reduced, and hydraulic gradients become more uniform due to improved moisture infiltration and distribution. Screening bark into different size fractions results in more pore size homogeneity. Stratified systems result in decreased air:water extremes across the vertical profile than traditional systems. Water potential remained more constant in the upper profile of a stratified system. Applying irrigation multiple times per day decreased the intensity of volumetric water fluctuations.

Peat use in horticulture continues to be scrutinized as consumers are becoming increasingly aware of the environmental sustainability concerns associated with peat. Thus, the horticultural industry is driven to search for peat alternatives. Substrate stratification (i.e., vertical layering of unique media atop another in a singular container) has been studied in nursery substrates and has demonstrated improved resource efficiency with regard to water and fertilizer inputs. However, minimal research has evaluated using the concept of stratified substrates as an attempt to reduce peat inputs in greenhouse production. Hence, the objective of this study was to identify if stratifying costly floriculture media atop of low-cost pine bark can reduce peat use, reliance, and cost within the floriculture industry. A floriculture crop, Petunia hybrid ‘Supertunia Honey’, was grown in two distinct substrate treatments: 1) nonstratified (commercial peat-based floriculture substrate) and 2) stratified peat-based substrate layered atop aged pine bark (1:1 by volume) under two different irrigation schedules. Crop growth was evaluated, including growth indices, shoot physiological responses, and root growth measurements. Substrate hydraulic properties such as matric potential and volumetric water content were monitored over time. The results demonstrated that a petunia crop can be produced in stratified substrate systems and yield similarly sized and quality crops as traditionally grown plants. Furthermore, the stratified substrate-produced crop had improved root productivity, yet less bloom, when compared with nonstratified-grown crops.

Industrial insect rearing is expected to increase as a feedstock to meet growing global food demand. This will lead to greater production of insect excreta known as frass, a nutrient-dense organic material that has shown promise as a natural fertilizer source with potential environmental benefits. In this study, black soldier fly (Hermetia illucens) frass (BSFF) was compared with a synthetic fertilizer (SF) during production of containerized ornamentals grown under greenhouse conditions. Fertilizers were incorporated into a bark-based substrate at 0, 0.1, 0.2, or 0.3 kg⋅m–3 nitrogen (N) planted with coleus (Plectranthus scutellarioides) plugs. Growth index, shoot dry weight, and leaf quality were assessed for a period of 6 weeks. In addition, coleus fertilized at 0.3 kg⋅m–3 N and a control had leachate collected and analyzed weekly for volume, pH, electrical conductivity, and nutrient losses. Black soldier fly frass was found to produce marketable coleus plants at 0.3 kg⋅m–3 N and reduce cumulative N leaching by 87% compared with coleus fertilized with SF at the same rate. Therefore, BSFF can be a suitable fertilizer source for coleus production without compromising growth and leaf quality while potentially decreasing nutrient leaching losses.

Mulching landscape beds is a common task for landscapers seeking to affect soil conditions and reduce weed pressure. This study investigated the effects of three pine (Pinus sp.) straw mulch depths (5, 10, and 15 cm) on soil moisture/temperature modulation during late winter/spring. No differences in soil volumetric water content were observed; however, increasing mulch depth to ≥10 cm decreased fluctuations in temperature. This research provides a better understanding of the effect of mulch depth and potential environmental benefits so that landscape contractors can determine cost-benefits of mulching applications.