About · Spongy Mesophyll Technologies

Built by vineyard owners for vineyard owners.

We're a vineyard technology company working quietly alongside growers in California, Oregon, Mexico, Italy, Armenia and beyond. Our founders grow and make wine; this product is the one we wished existed.

01 · Our Story

Twenty years of spreadsheets, pinned to a wall.

Sentinel was born from a simple observation: the world's finest vineyards were making critical decisions from clipboards, Excel workbooks, and memory.

Our team had spent years walking vineyard rows—scouting for Leafroll, flagging Red Blotch symptoms with plastic tape, guessing at cluster counts, and watching the institutional knowledge walk out the gate every time a crew foreman retired.

Drones and satellites promised a solution, but NDVI maps stop at the canopy. A vine with Red Blotch can look identical to a shaded, under-irrigated, or simply young vine from above. The ground truth—the actual condition of the plant—was still trapped in peoples' heads.

What we built.

Sentinel is an end-to-end vine-level management system. Drop every vine once with sub-centimeter GNSS. Attach disease status, phenology, yield estimates, photos, and lab results. Issue vine-specific work orders that auto-update as work is completed. Analyze trends across vintages.

We operate out of Spongy Mesophyll Technologies—named for the layer of leaf tissue where photosynthesis, transpiration, and most pathogens quietly do their work. Invisible, essential, and the foundation of everything above.

02 · Principles

What we believe about vineyard data.

01

Ground truth beats aerial guesses.

A vine's condition is something a human confirms, not an algorithm. We build tools that make confirming fast—not tools that pretend pixels are plants.

02

Data has to live longer than crews.

Vineyards outlive employees. The institutional memory of which vine was grafted when, and why, has to survive in a system—not a crew foreman's head.

03

Precision is a practice, not a product.

Sub-centimeter accuracy is meaningless if the workflow around it is painful. We obsess over the walk-up loop: the vine, the phone, the record, back to work.

03 · Leadership

Napa meets Silicon Valley.

Shawn DeMartino
CEO & Co-Founder

Shawn DeMartino

Shawn is the General Manager of Grace Family Vineyards in St. Helena, with prior viticulture roles at Harlan Estate and Screaming Eagle. As Director of Viticulture he pioneered the development and implementation of Sentinel's vine mapping technology. Shawn leads the company's strategic direction, sales and user engagement, as an expert in all things vineyard and wine related. He graduated from Harvard University in 2014.

Currently
General Manager · Grace Family Vineyards
Prior
Harlan Estate · Screaming Eagle
Education
Harvard, A.B. '14
Christian Sidak
CTO & Co-Founder

Christian Sidak

Christian Sidak co-founded Spongy Mesophyll Technologies with Shawn in January 2023. Before, Christian worked as a product manager and engineer at Palantir Technologies, an enterprise software company, developing new AI products in the defense and healthcare sectors. At Spongy Mesophyll Technologies, Christian shapes the technical and engineering decisions of the company and translates user needs into code applications. He graduated from Harvard University in 2017.

Prior
Palantir Technologies
Education
Harvard, A.B. '17
Languages
Eleven, and counting
04 · Contact

Tell us about your vineyard.