Cherry, olive, persimmon, peach, mandarin, Scots pine and city street trees. Fourteen months of independent, peer-reviewed results — including the ones that complicate the picture.
Ten peer-reviewed papers using microtensiometers have appeared in the last fourteen months. We did not write any of them. They come out of Spain, Italy, Chile, Germany and the United States, they cover seven crops plus forestry and urban trees, and between them they take up the three questions growers actually put to us: does it agree with the pressure chamber, does it catch anything a spot measurement misses, and does it work in something other than almonds.
We host the PDFs on our resources page. Below is what they found — including the parts that cut against the technology.
Against the pressure chamber
The Scholander pressure chamber is the reference method for plant water status. It is accurate, it is slow, and someone has to walk the block at solar noon to use it. Three of these papers ran a microtensiometer beside one.
In Spain’s Jerte Valley, a sweet cherry study across a range of altitudes reported R² ≈ 0.72 between the two:
The strong correlation observed between Ψtrunk measured by microtensiometers and Ψstem determined with a pressure chamber (R² ≈ 0.72; Fig. 10c) confirms the robustness of this technology for real-time assessment of tree water status and irrigation management in sweet cherry. […] To our knowledge, this study represents the first demonstration of the suitability of microtensiometers for continuous monitoring of trunk water potential in commercial cherry orchards.
A Chilean sweet cherry trial under regulated deficit irrigation put the correlation at R² = 0.81 and went a step further, using the sensor to steer the irrigation itself:
The MT provided continuous and accurate measurements of stem water potential that correlate strongly with pressure chamber measurements within the SWP range of -1.3 to -0.4 MPa. […] This study confirms the reliability of MT as a tool for monitoring SWP and guiding water-saving irrigation practices aimed at improving water productivity in commercial orchards under Mediterranean climate conditions.
And well outside horticulture, a forestry group tracking drought in Scots pine reported R² = 0.78 against leaf pressure-chamber readings, describing the comparison as validating both instruments at once.
Three studies, three crops, three continents’ worth of climate, and correlations in the 0.72 to 0.81 band. That is a reasonable summary of where the method stands — not perfect agreement, and nobody claims otherwise.
What continuous catches that a spot check misses
Agreement with the chamber is the wrong question to stop at, because the chamber is a handful of readings a season. The more useful question is whether continuous measurement resolves differences a spot check cannot.
An olive study under Mediterranean conditions compared microtensiometers against thermal indicators and periodic pressure-chamber readings, across full and deficit irrigation:
The MTs were able to detect significant differences between irrigation regimes (p-value < 0.05, resulting in average values of −0.78 ± 0.20 MPa and −1.09 ± 0.27 MPa under FI and DI, respectively), while thermal indicators and SWP measurements occasionally identified these differences.
A persimmon rootstock study reached the same conclusion from the other direction, ranking continuous trunk water potential against canopy reflectance:
Among the evaluated indicators, continuous Ψtrunk measurements provide the most reliable information on plant water status, whereas canopy reflectance indices are less sensitive to short-term stress changes.
Short-term is the operative phrase. A stress event that starts on Tuesday and resolves by Friday is invisible to a method that samples every second week.
Seven crops, and then some
Most of our own network is almonds, prunes and wine grapes. This literature is not. Sweet cherry appears twice. There is a mandarin study — Citrus reticulata under Mediterranean conditions and several irrigation regimes — concluding that the method is suitable for continuous stem water potential monitoring in that crop (Vaccaro et al. 2025, Agricultural Water Management). There is olive, persimmon and peach. There is Pinus sylvestris in a drought-hydraulics study that has nothing to do with irrigation scheduling at all (Cachinero-Vivar et al. 2026, Trees).
And there is a review of drought-stress detection in urban trees — the ones in the sidewalk cutouts on your street — which rates the method on a criterion no orchard paper bothers with: how much work it is to live with. Its verdict was one line. “The microtensiometer has the easiest usability once it is installed” (Hörmann et al. 2025, Hydrological Processes). The same review notes the sensor reads one tree and is invasive to install, which is fair.
The next question is prediction
One paper points somewhere different. A group working in peach trained machine-learning models to predict trunk water potential ahead of time, using microtensiometer data as the input — and named the sensor in the title.
Advanced technologies, such as FloraPulse microtensiometers, offer an innovative solution by enabling accurate, real-time monitoring of plant water status by measuring Trunk Water Potential (TWP).
Their 6, 12 and 24-hour prediction horizons all landed above R² 0.89. The caveats are the authors’ own and they matter: one season, eight trees, every one irrigated at 100% of ETc. This is a first stage, not a finished tool. But the direction is the interesting part — measurement was the hard problem, and once it is solved well enough, people start trying to forecast it. We are working on the same problem across our own network.
What the field is still arguing about
Two of the ten papers are not results at all. They are the field taking stock, and they are the reason this roundup is worth reading rather than a press release.
A perspective piece in the Journal of Plant Hydraulics asks directly whether microtensiometers can move plant science beyond the Scholander chamber. Its answer is not a straight yes:
Micro-tensiometers have the potential to be a promising addition to the water status toolbox, though their adoption requires reconciling their particular advantages, disadvantages, and lingering questions.
An addition to the toolbox. Not a replacement for the chamber — the piece is explicit that no single instrument takes over, and it works through cost, durability and wounding at length.
The other is a 19-author best-practices review in New Phytologist covering continuous water-potential sensing as a whole. It sets out the advantages plainly, and it lists the limitations just as plainly:
Microtensiometers provide continuous, nondestructive, direct measurements of plant water status and are embedded directly into the stem or trunk, minimizing excess tissue injury that could affect readings […] Compared with psychrometers, they are relatively easy to install, monitor, and maintain, with typical installation times in the order of minutes, and offer cost advantages at comparable levels of uncertainty.
Ten papers in fourteen months, most of them from people with no stake in whether the technology succeeds, several of them pointing at real limits. That is roughly what a measurement method looks like on its way from a lab curiosity to an instrument — argued over in public, tested in crops its makers never planned for, and not yet finished.
About the papers: Every study linked here is independent work by outside researchers, hosted in full on the
FloraPulse research library.
Quotations are verbatim; a bracketed ellipsis marks text joined from the same section of the original.
Written by the FloraPulse team in Davis, California, where we build the sensors these groups are testing.