Autonomous or Robotic Mower Use on Florida Lawns

Introduction

Mowing is one of the most important cultural practices for the maintenance of a healthy lawn. This publication serves as a practical guide for homeowners and lawn care professionals, providing information on effectively implementing autonomous and robotic mowing technologies on lawns. Proper mowing height and intervals increase turfgrass density, leading to healthier turf that is more competitive against weeds, diseases, and insects (Patton 2025; Trenholm et al. 2018). Traditional mowing is generally performed with a gasoline engine or corded electric-powered lawn mowers. More recently, the use of battery-powered lawn mowers is increasing. Similarly, autonomous or “robotic” mowers have been gaining popularity for their various benefits. The robotic lawn mower market was valued at USD 351.14 million in 2021 and is expected to reach USD 704.55 million by 2027 (Arizton Advisory and Intelligence 2022).

Autonomous mowers are designed to reduce labor and operator injury risk during mowing operations compared to traditional mowers. Additionally, autonomous mowers reduce gas emissions, dust production, and noise pollution, providing environmental benefits (Grossi et al. 2016; Pirchio et al. 2018a). Although there are many different brands and models in the market with varying features, a lot of autonomous mowers come with a boundary wire that delineates the mowing area and a docking station that allows for automatic charging. In recent years, real-time kinematic (RTK) positioning, a satellite navigation technique, has become more commonplace. Different types of robotic mowers have different markets and niches. For example, semi-autonomous mowers could be used by landscape companies or in public areas like parks where you can leave a charging station.

Research has shown that autonomous mowers can reduce energy consumption compared to gasoline-powered mowers. While the autonomous mower's working time can be ten times greater than a traditional gasoline-powered mower, the estimated energy consumption for an autonomous mower may be three times less than a gasoline-powered mower (Grossi et al. 2016; Pirchio et al. 2018b). Since they are lightweight, robotic mowers also minimize soil compaction compared to heavier mowers, helping to maintain healthier turfgrass root zones (Luglio et al. 2023).

Autonomous Mower Operation

As noted, autonomous mowers generally operate within the confines of a boundary wire that is buried around the perimeter of the area to be mowed. This wire can be installed before sod installation or inserted into established turf by simply opening a narrow furrow with a square-pointed shovel, straight hoe, or machete. Some of the more advanced autonomous mowers do have GPS capabilities that can facilitate movement from one area to another (e.g., front yard to back yard), provided a clear path or corridor is accessible. Some mowers also use a direct path guide wire back to the docking station.

Although autonomous mowers will mow where they are placed, making some changes can improve their efficiency. For example, most landscapes have elevated landscape beds or borders where the mower cannot reach, causing grass to grow tall. Consequently, these edges are typically trimmed with a string trimmer. By lowering the elevation of hardscape materials, the autonomous mowers can “overlap” these areas and reduce the need for string trimming.

Mowing Strategies

Conventional lawn mowing typically involves the operator starting at one edge of the lawn and systematically making overlapping passes until reaching the opposite side. With robotic mowers, there are generally two primary mowing strategies:

1. Random Trajectory: In this method, autonomous mowers navigate the lawn randomly, which is an efficient solution to mowing areas with a variable number of obstacles (Sportelli et al. 2020). However, this operating scheme generates frequent overlapping, which decreases the operational efficiency of the mower (Sportelli et al. 2021).
2. Systematic Trajectory: Alternatively, this method utilizes structured, pre-planned mowing patterns such as straight lines or grids. This method is typically employed on well-maintained, obstacle-free lawns. Systematic trajectories have been shown to significantly enhance operational efficiency, reaching approximately 80%, by reducing unnecessary overlapping (Sportelli et al. 2021). While systematic trajectories can increase wheel marks, the study did not find many differences in turfgrass quality between the two systems (Sportelli et al. 2021).

Weed Pressure

Research has shown that autonomous mowers can reduce spontaneous weed percent cover compared to rotary mowers (Grossi et al. 2016). Creeping-type weeds, such as Trifolium repens (white clover), Trifolium subterraneum (subterranean clover), and Lotus corniculatus (birdsfoot trefoil), exhibited increased growth under autonomous mowing regimes. The consistent mowing height of autonomous mowers allowed these species to grow laterally beneath the mowing height, leading to larger weed diameters compared to areas mowed with traditional rotary mowers (Pirchio et al. 2018a). However, increased white clover abundance may be considered positive if a mixed-species lawn is desired.

Quality of Cut

A general guideline for mowing is to mow often enough that no more than one-third of the leaf blade is removed per mowing event, which is typically once per week for most lawn grasses. Autonomous mowers typically use very small, two-edged, razor-type blades that are affixed to a spinning disk (Figure 1). These blades are small (<1.5″) compared to traditional mowers (~20″). The cutting swath of an autonomous mower is generally <12″ even though the mower deck is similar in size to a traditional mower. When setting up an autonomous mower, one typically inputs the square footage of the lawn. The onboard computer calculates the run times necessary for the mower to cover the area based on battery life and other factors. As such, autonomous mowers generally run on a daily basis. The cutting head reverses its direction of spin at each mowing event. The small cutting edge of the razor blade in autonomous mowers can improve cut quality (i.e., cleaner cut), decreasing leaf chlorosis (i.e., yellowing) and turfgrass stress from mowing (Pirchio et al. 2018a; Shaddox et al. 2020). Additionally, autonomous mowers can increase turf density and decrease average leaf width, resulting in higher turfgrass quality (Grossi et al. 2016; Pirchio et al. 2018a). Our experience shows that the quality of cut will decline after one or two months of use, and the blades should be regularly replaced (i.e., every six to eight weeks) during the growing season.

Experience with Warm-Season Grasses

The two main components of mowing are cutting height and frequency. Both factors depend on the one-third guideline, turfgrass species, cultivar, and level of desired lawn quality (Trenholm et al. 2018). Most autonomous mowers were developed for the European market, where cool-season grasses (i.e., fescues, ryegrasses, and bluegrasses) are dominant. These cool-season turfgrasses are mowed at heights of <2.5″, and most models of robotic mowers do not exceed this cut height. St. Augustinegrass, a common turfgrass for Florida, is mowed relatively high (i.e., 2.5″–4″) because it has coarse-textured leaf blades (Trenholm et al. 2018).

St. Augustinegrass

In 2018, a study was conducted at the UF/IFAS West Florida Research and Education Center in Jay, Florida, to determine if ‘Floratam’ St. Augustinegrass (Stenotaphrum secundatum [Walter] Kuntze) could be maintained at 2.4″ when using a robotic mower (Boeri et al. 2023). The robotic mower was set to mow daily at a height of 2.4″ between the hours of 9 a.m. and 3 p.m. on their respective plots. For comparative purposes, a conventional mulching mower set at 3.5″ was used to mow plots on a weekly basis, simulating standard maintenance practices. The mowing pattern was alternated weekly.

During the spring and fall months, St. Augustinegrass exhibited greater uniformity and a greater green cover when using the autonomous mower compared to the quality and height of turfgrass when using the traditional mower. The autonomous mower also prompted a later winter dormancy and an earlier spring green-up (Figure 2). While canopy temperature was not recorded in this study, lower mowing heights tend to increase surface temperatures, which would explain the phenomena.

Similar to studies conducted on tall fescue (Festuca arundinacea) (Shaddox et al. 2020), the razor blades of the autonomous mower provided better cut quality, which minimized fraying and subsequent browning in St. Augustinegrass (Figure 2). We observed wear patterns in the autonomous mower plots, particularly near the docking station. As described by Sportelli et al. (2021), elliptical wear patterns from excess tracking and turning in the corners were also present (Figure 3).

Operational Considerations for Autonomous Mowers

1. Equipment Maintenance: Florida has a high incidence of lightning strikes, and we have observed damage to our equipment as a result. The mowers themselves have not been damaged, but the docking/charging stations have needed replacement. While the mowers themselves have a good lifespan, routine maintenance would be helpful, including periodic blade replacement, battery monitoring/replacement, and general software updates to ensure consistent performance.
2. Red Imported Fire Ant Issues: We have also observed a high level of red imported fire ant mounding in the docking stations. It is well-known that fire ants are drawn to electrical equipment, and the docking/charging stations are not immune. Routine fire ant insecticide treatment around the docking station is highly recommended.
3. Security and Theft: Autonomous mowers, being unattended outdoor devices, are susceptible to theft. However, many mowers require entering a security code to access the programming functions. Without that code, the stolen mower will be inoperable. Higher-end models can be located remotely should they be stolen.
4. Obstacle Navigation: Robotic mowers are designed to effectively navigate obstacles by changing their direction upon encountering items. They can typically handle smaller objects left on lawns without sustaining damage to their cutting mechanisms. Similarly, pet feces generally do not pose a problem for the robotic mowers.
5. Weather Resilience: The autonomous mowers typically operate regardless of rain conditions. We have not observed any negative effects of the mowers operating during rainy conditions. Some of the newer advanced models have detection systems onboard that delay mower operations.

Conclusion

Autonomous mowers are becoming more commonplace in the landscape. Many homeowners are deploying this technology, and some companies now market lawn care services using autonomous mowers. These companies typically install the mower and then provide routine inspection of the equipment, ensuring that it is operating properly. Some newer mowers allow these companies to remotely monitor the equipment through internet connections.

References

Arizton Advisory and Intelligence. 2022. Robotic Lawn Mower Market—Global Outlook & Forecast 2022–2027. https://www.arizton.com/market-reports/us-robotic-lawn-mower-market

Boeri, P. A., A. J. Lindsey, and J. B. Unruh. 2023. “Autonomous Compared with Conventional Mower Use on St. Augustinegrass Lawn Quality.” HortTechnology 33 (4): 377–380. https://doi.org/10.21273/HORTTECH05206-23

Grossi, N., M. Fontanelli, E. Garramone, et al. 2016. “Autonomous mower saves energy and improves quality of tall fescue lawn.” HortTechnology 26 (6): 825–830. https://doi.org/10.21273/HORTTECH03483-16

Luglio, S. M., M. Sportelli, C. Frasconi, et al. 2023. “Monitoring Autonomous Mowers Operative Parameters on Low-Maintenance Warm-Season Turfgrass.” Applied Sciences 13 (13): 7852. https://doi.org/10.3390/app13137852

Patton, A. J. 2025. “Why mow?: A Review of the Resulting Ecosystem Services and Disservices from Mowing Turfgrass.” Crop Science 65 (1): e21376. https://doi.org/10.1002/csc2.21376

Pirchio, M., M. Fontanelli, C. Frasconi, et al. 2018a. “Autonomous Mower vs. Rotary Mower: Effects on Turf Quality and Weed Control in Tall Fescue Lawn.” Agronomy 8 (2): 15. https://doi.org/10.3390/agronomy8020015

Pirchio, M., M. Fontanelli, C. Frasconi, et al. 2018b. “Autonomous Rotary Mower Versus Ordinary Reel Mower—Effects of Cutting Height and Nitrogen Rate on Manila Grass Turf Quality.” HortTechnology 28 (4): 509–515. https://doi.org/10.21273/HORTTECH04064-18

Shaddox, T. W., G. Munshaw, and K. Cropper. 2020. “Cut Quality of Turfgrass Leaves as Influenced by Robotic and Rotary Mowers.” ASA, CSSA, and SSSA International Annual Meetings. https://tic.msu.edu/tgif/flink/RECNO/315102

Sportelli, M., M. Fontanelli, M. Pirchio, et al. 2021. “Robotic Mowing of Tall Fescue at 90 mm Cutting Height: Random Trajectories vs. Systematic Trajectories.” Agronomy 11 (12): 2567. https://doi.org/10.3390/agronomy11122567

Sportelli, M., M. Pirchio, M. Fontanelli, et al. 2020. “Autonomous Mowers Working in Narrow Spaces: A Possible Future Application in Agriculture?” Agronomy 10 (4): 515. https://doi.org/10.3390/agronomy10040553

Trenholm, L. E., J. B. Unruh, and J. L. Cisar. 2018. “Mowing Your Florida Lawn: ENH10/LH028, rev. 6/2018.” EDIS 2018 (3). https://doi.org/10.32473/edis-lh028-1991