One of the questions we get most from wine grape growers and researchers is the same one we ask ourselves every season: how well does the FloraPulse sensor really track the pressure chamber?
This summer, a team at the Research Centre Laimburg in South Tyrol, Italy answered that question for two of the most widely planted white grape varieties in Europe — and the answer was R² = 0.968.
The trial
During the 2024 growing season, Florian Haas and colleagues installed FloraPulse sensors on Sauvignon Blanc and Chardonnay vines in a research vineyard in Kaltern (Bolzano). The season started wet and then turned hot and dry from July onwards — a textbook stress year. Across eight Scholander pressure-chamber measurement sessions, the team compared midday stem water potential against the FloraPulse readings on the same vines.
The correlation between FloraPulse and the pressure chamber was strong (R² = 0.968) and statistically significant. The sensor also picked up the well-known difference in how the two varieties respond to drought: Sauvignon Blanc behaved isohydrically (closing stomata earlier to defend water potential), while Chardonnay behaved anisohydrically (letting water potential drop further before responding).
Why it matters
Stem water potential is the gold standard for plant water status — it’s the number that decades of irrigation thresholds, deficit-irrigation strategies, and wine-quality research are built on. The pressure chamber is accurate, but it’s a once-a-week snapshot taken by a trained person at midday. FloraPulse delivers the same number, automatically, every 20 minutes, all season long.
Independent confirmation from a research institute we have no commercial relationship with — published as a flash oral at the 23rd GiESCO International Meeting in Geisenheim — is exactly the kind of validation we want growers to be able to point to when they’re deciding whether to trust a continuous sensor for irrigation decisions in high-value white wine grapes.
Read the full abstract
Haas F., Martinelli J., Schmid A., Wenter A., Thalheimer M., Raifer B. (2025). Innovative water status monitoring of white grape varieties with on-plant sensors. GiESCO 2025, Geisenheim, Germany.
Read the abstract on IVES Open Science →
If you’re considering FloraPulse for your vineyard or research program, get in touch — we’d love to talk.