Quinta das Abelhas – Spring update
Published on: June 16, 2021
The Spring of 2021 marks a drastic change in Quinta das Abelhas, a project reNature has been supporting since last winter. Buds have long opened up, and now in late spring, the saplings planted during November have all exploded (vegetatively speaking). Though the surrounding landscape is turning brown again, the large diversity of plants nurtured by Marc are maintaining this pilot farm green. Annual crops that provide an early yield from the system are already being harvested and more are being planted. Quinta das Abelhas project is executed and run by Marc Leiber / GrowBack, according to the advice and consultancy of Ernst Götsch / Agenda Götsch, who created the plantation design of Syntropic farming adapted to the Mediterranean climate used on this test farm.
Surviving winter frost and spring drought
Though the transition from winter to spring and summer in this region is always marked by radical drying of the winter and spring vegetation, leaving the landscape golden and brown in colour, this particular spring brought very little significant rainfalls since March 13th. However, stable and cool temperatures have allowed the moisture stored in the soil from winter to stay for longer and the green vegetation of winter to persist for longer. Most trees established well, even in fields without irrigation. According to Marc, this can be reattributed to the large diversity of annual plants that were seeded in their surroundings and managed in various moments during winter and spring.
Some trees did suffer due to strong winter frosts, and two unusually late frost events stunted the new growth of young trees (one week at the end of march and three nights at the beginning of May). Now, as we enter June, temperatures begin to rise, and the available humidity continues to decrease, the plants will be put to a new challenge and we will be able to find out whether our work paid off or not.

Harvesting, seeding, and orchard maintenance
Designed to provide an early income, Marc incorporated annual crops in the plantations to allow for a spring harvest. And the time has come for Marc to reap the (early) rewards of his planting: broccoli, cauliflower, strawberries, broad bean, peas, lettuce, cabbage, potato, and more, are ready for harvesting. Marc and the volunteers have ample to consume for themselves and Marc can additionally sell some of his products to the local market.
With the first harvest of annual crops done, seeding for a new batch of crops is already underway. Tomatoes, pumpkins, sunflowers, beans, melons, corn, cucumber, basil, chilly pepper, bell pepper, and more are being sown around this time.
Meanwhile, Marc is performing maintenance for the benefit of the trees: mowing green manure in between tree rows, applying straw to the tree lines as mulch, weeding in tree lines, stimulative pruning of young trees, are all part of the activities performed during this time.

First open day of the year
May 8th marked the first open day of 2021 and was organised by Freixo do Meio, the estate that hosts Marc’s farm. Visitors from a diverse background came to visit and observe Marc’s forest-in-the-making. The visitors first received a small introduction to the project, with images of how the land looked before the interventions, and then were able to independently explore the farm. After this walk all visitors gathered in the shade of an oak tree to discuss what they observed and get answers to questions and doubts they had from Marc.
Researching soil water and temperature and aboveground biodiversity on the site
Though some delay in starting with monitoring and evaluation occurred, reNature is taking steps to capture the impact of the farming system on a range of environmental key performance indicators (KPIs) at the farm.
LoRaWAN and IoT; pardon me?
You may have heard of “smart farming” or how the Internet of Things (IoT) is revolutionizing the way agriculture and agroforestry are monitored and managed by wirelessly connecting things like remote sensors (or even robots, drones etc.) and the data they collect in real time to the internet via gateways. Long range (LoRa) monitoring over a wide area network (WAN) is making this possible and the possibilities are endless.
We’re excited to continue working with Farm21 to measure soil moisture and temperature using in-situ sensors. Measuring these parameters will deliver important insights into the effects of the plantation, species layout composition, and their management on the micro-climate.
Nonetheless, pioneering new technology always brings challenges and we hope to share the learnings from this project. For example, troubleshooting a non-functioning signal between the gateway and soil sensors took longer than expected. Due to the fact that in this particular location, trees and landscape are likely blocking the LoRa signal. A solution has to be developed to power the gateway connecting to the sensors using a solar panel and battery pack.
Listening to the landscape
In addition to soil water and temperature, aboveground biodiversity will be measured on the farm using bioacoustic monitoring. AudioMoth devices will be placed in Marc’s fields as well as in a reference area in the surrounding landscape in order to record and analyse sounds from animals (for instance, songs from birds). We will be able to see how several indicators of bird diversity (e.g. species richness, relative abundance) evolves through time as well as how sounds compare between different agro-ecosystems.
Bioacoustics monitoring provides systematic and scientifically-sound ways to record animals’ songs and vocalisations. The automated analysis of this non-intrusive continuous recording results in animal diversity indices which have shown to be able to serve as proxies for overall species diversity. Cutting-edge machine learning technologies can even allow for individual species recognition where these individual species are relevant target species!
For instance, functioning as a general proxy for biodiversity, assessing bird communities is an affordable and widely-used way to indicate the general status of a site’s biological diversity, and can well represent the diversity of other vertebrate species. Indeed, also for agroforestry systems, bioacoustics monitoring (or, ‘soundscape acoustics monitoring’) seems a promising low-cost solution to quantifying the impacts of agroforestry systems on habitat conservation.
