The GROW Citizen Observatory was developed in a Horizon 2020 funded project to engage citizens (interested in growing food and improving the health of their soils) in sharing their data with a large community of growers across Europe.

Grow © Arūnas Naujokas | Unsplash

The GROW Citizen Observatory ran as a three-year project, during which 22 GROW communities across 13 European countries were connected via the GROW network. The growers took part in a large experiment, collectively gathering data from more than 6,500 low-cost ground-based soil moisture sensors to measure the water content of their soils. This citizen observatory represents the first continental wide monitoring program of soil moisture, carried out over an extended period of time and at a much higher spatial density than was previously undertaken. The objective was to provide ground-truth data to help validate soil moisture from satellites, in particular, Sentinel-1. Through such a validation exercise, the accuracy of predictions of extreme events such as floods and drought can be improved. You can read about these experiments in Kovács et al. (2019), Xaver et al. (2019) and Zappa et al. (2019, 2020). The soil moisture time series data set, which also includes temperature and light levels, has been made openly available for users to download and experiment with, available from here.

The GROW Citizen Observatory also developed a mobile app to provide citizens with information about growing edible plants as part of a larger movement of supporting citizens with growing advice, engaging them in testing out different regenerative food growing techniques, helping them to improve their soils, and raising their awareness of issues related to land use, climate change and sustainability. The edible plant database provides information on planting and harvesting dates based on data collected from the citizens as well as information from seed packets and the literature, which is available from here.


Kovács, K. Z., Hemment, D., Woods, M., et al. (2019). Citizen observatory based soil moisture monitoring – the GROW example. Hungarian Geographical Bulletin, 68(2), 119-139,  

Xaver, A., Zappa, L., Rab, G., Pfeil, I., Vreugdenhil, M., Hemment, D., Dorigo, W. (2019). Evaluating the suitability of the consumer low-cost Parrot Flower Power soil moisture sensor for scientific environmental applications. Geosci. Instrum. Methods Data Syst,

Zappa, L., Woods, M., Hemment, D. Xaver, A. and Dorigo, W. (2020). Evaluation of remotely sensed soil moisture products using crowdsourced measurements. Proc. SPIE 11524, Eighth International Conference on Remote Sensing and Geoinformation of the Environment (RSCy2020), 115241U (26 August 2020),

Zappa, L., Forkel, M., Xaver, A. and Dorigo, W. (2019). Deriving Field Scale Soil Moisture from Satellite Observations and Ground Measurements in a Hilly Agricultural Region. Remote Sensing, 11(22), 2596,


Ajates, R., Hager, G. , Georgiadis, P., Coulson, S., Woods, M., & Hemment, D. (2020). Local Action with Global Impact: The Case of the GROW Observatory and the Sustainable Development Goals. Sustainability 12 (24) e10518. 10.3390/su122410518.

Kovács, K.Z., Hemment, D., Woods, M., van der Velden, N., Xaver, A., Giesen, R., Burton, V., Garrett, N., Zappa, L., Long, D., Dobos, E., & Skalsky, R. (2019). Citizen observatory based soil moisture monitoring – the GROW example. Hungarian Geographical Bulletin 68 (2) 119-139. 10.15201/hungeobull.68.2.2.

Moorthy, I., Fritz, S. , See, L. , Wehn, U., Hemment, D., Pau, J.M., Tsertou, A., Vohland, K., Ferri, M., McCallum, I. , Domian, D., Hager, G. , & Perger, C. (2018). WeObserve: An Ecosystem of Citizen Observatories for Environmental Monitoring. In: European Geosciences Union General Assembly 2018, 9-13 April 2018, Vienna, Austria.