Regenerative Viticulture Series

Regenerative Viticulture Insights: Discussing vine nutrition and soil health with Sergio Nicolau

Regenerative Viticulture Insights: Discussing vine nutrition and soil health with Sergio Nicolau 1050 1313 Sectormentor


Regenerative Viticulture Insights: Discussing vine nutrition and soil health with Sergio Nicolau

We recently shared three amazing discussions from our second edition of the Regenerative Viticulture Series.

To celebrate our learnings, we’re releasing a roundup of each of the sessions and some of our favourite insights from them. In our first instalment we pulled together some highlights from our conversation with the brilliant Mimi Casteel which you can read here. Our next conversation was with Sergio Nicolau, a leading light in the regenerative viticulture world with a deep understanding of plant and soil biology.

Sergio is a 5th generation farmer based in Torres Vedras, Portugal. Sergio’s extensive knowledge is a result of many years of experience as farm manager plus working within his family’s vineyard and winery, coupled with his studies in conventional agronomy. In 2018 Sergio converted the vineyard to organic production after beginning to understand the detrimental effect conventional agricultural practices are having on the health of the environment. He has been studying ways in which to increase the health of his farm’s ecosystem ever since, learning from regenerative agriculture experts such as Gabe Brown and Nicole Masters and implementing these practices on his land. 

One of these practices was to establish cover crops in the alleyways between the vines. Sergio takes diversity to the next level, advancing from his previous mix of 12 species from three plant families to 16 species from 6 different families including: grasses such as ryegrass and black oats; legumes including four different clovers, alfalfa and vetch; mustards, turnips, radishes, beets, spinach; and plants that will encourage pollinators such as buckwheat, calendula and phacelia.

Sergio found that changing the cover crop mix to one that is more diverse has made a big difference to his soil health. Before implementing cover crops the vineyard experienced issues with soil runoff during periods of heavy rainfall. Cover reduces this through slowing down the individual rain droplets, intercepting them before they hit the soil; while the roots act as an anchor, holding soil aggregates in place, reducing erosion and nutrient loss. A diversity in root architecture enhances these benefits as it allows for more layers of soil to be penetrated, improving structure through breaking up compaction layers and opening up pores in the soil allowing water to infiltrate more effectively. 

Sergio also uses his neighbours sheep to graze his covers during winter when the vines are dormant using holistic planned grazing practices. This maintains the growth of his cover crops, while improving soil and vine health by introducing a source of organic matter and nutrients through the sheep manure.


Pictures of soil run off from the neighbouring vineyard without covers crops (left), and Sergio’s vineyard with cover crops established both in-between and under vines rows (right)


Sergio goes on to explain how encouraging a diverse range of plant species will also benefit the biological health of the soil

“It all starts with photosynthesis and the end product which is sugars.” Sugars go to three main points in a plant: the shoot tips, fruit and the excess goes to the roots. Meaning the higher your photosynthetic capacity the more root exudates are released into the soil, feeding the biology within it. Diversity is key here for a few reasons, firstly diverse mixes will grow plants of varying heights with different leaf sizes and shapes that can capture more sunlight at all levels. Secondly, “the more varied your species, the more varied your root exudates – different plants feed different biology and it’s this diversity that is important”. 

Sergio also discussed the effect different plant species have on the redox potential of the soil, creating either disease suppressive or disease enhancing soils. Some plants are more oxidative, such as GMO (modified species), whilst species such as clovers, black oats or mustard are more reductive. He states that it is good to experiment with a diverse range of covers in order to find out which species work in your system: “Now I have learned enough to know that the next mix will be different and maybe I do not have to grow as many species, just the right ones”. 

“Cover crops are a very good tool to start, to give a boost to the system, but then the natives come and it is like a natural succession – often times the natives are better as they are more resilient”

It is amazing to see that despite being in very arid conditions the ground cover in Sergio’s vineyard is extremely healthy, green and lush! A testament to his management.


                              Picture of a diverse, species rich cover crop established in Sergio’s vineyard

We then took a dive into plant nutrition, discussing some amazing findings from experiments within his own vineyard

It is believed that nutrition is a key factor to plant immunity, the more balanced nutrition a plant has the more resilient they become to pests and diseases. It was during an insect attack on his vines that Sergio really saw the power of increased nutrition. Being certified organic meant Sergio was compelled to search for alternative approaches to the use of insecticides. He found that insects have simple digestive tracts and cannot digest complex proteins or amino acids. If you increase the presence of these compounds within a plant insects will stop seeing it as a food source. He found that molybdenum is a cofactor for the enzyme that reduces nitrates and allows nitrogen to form amino acids and complete proteins. After applying a spray of molybdenum, magnesium and sulphur, Sergio found that within two days the insects were no longer feeding on the vines having moved on to the weeds instead!

“Insects are the garbage collectors of nature, they come in and take out of the system plants that are not healthy. So if you have really healthy plants that do not have nitrates or simple sugars and are photosynthesising well, they will not look at the plant as food.”

Sergio now regularly measures the nutritional makeup of his plants using sap analysis in order to decide what nutrients to apply in his vineyard. This is not only useful to get a sense of the vines health and the extra help they may need, but also for understanding what sprays he should cut back on in order to improve nutrition. An excess of some nutrients may have an undesired affect, for example high levels of potassium will block other nutrients such as calcium and magnesium. While other nutrients will have a positive relationship with each other, meaning you may only have to apply one to get an increase in three nutrients. Sergio believes it is very important to understand these synergies in order to be efficient and economic with your applications.

Abby and Sergio discussed that although sap testing is often just a snapshot in time, the idea is that you’re improving the plants health in that moment, in turn increasing it’s photosynthetic capacity and its ability to feed soil biology. This will support the development of a healthy soil ecosystem, promoting long term health and resilience and reducing the need to apply these artificial foliar nutrients in the future.

“It’s like a feedback loop, if the plant grows more healthy, the more biology it will feed, and the more biology you create in the soil the less you need these nutrients.”


Pictures of soil tests performed in Sergio’s vineyard, observing topsoil depth and soil structure

Alongside conventional sprays Sergio is also experimenting with the best way to make and apply nutrients

Sergio has stopped buying commercial products of micronutrients in their oxidised form as he believes the plants will not be able to neutralise them as well. He instead does his own chelation at home using the raw nutrient mixed with a carbon source such as fulvic acid, molasses and seaweed to make nutrient extracts

He also produces additional extracts using more natural ingredients including seaweed, which is high in nutrients and provides beneficial hormones for the plants; plant extracts such as horsetail extract which is rich in silicon and fights fungal disease through drying out the leaves; and shrimp extract which helps boost plant immunity, furthering its resilience against disease. Sergio also discussed his use of fish hydrolysis within the vineyard which provides protein and organic nitrogen to the vines themself, while also supplying a good source of healthy fats which feed the fungal communities within the soil. 

Sergio uses two separate extraction methods to produce fish hydrolysis: when used as a soil fertiliser he will shred the fish waste and mix it with water, molasses and lactic acid; when aiming to create a foliar for the leaves he uses Korean Natural Farming techniques: mixing equal weights of fish waste and brown sugar. 

Abby and Sergio moved on to discuss the importance of building soils that are more fungal dominated in vineyards. Years of using conventional tillage and chemical fertilisers has decreased the fungal communities within Sergio’s soil, leaving it dominated by bacteria. To combat this Sergio uses both fish hydrolysis alongside a compost extract made using the Johnson-Su technique. Johnson-Su composting aims to grow a biologically diverse soil microbiome that is fungal dominated and applied to the soil as a microbial inoculant in the form of a liquid fertiliser. Sergio applies this in his vineyard using a sprayer and mixes in fish hydrolysis, humic acid and micro nutrients to act as food for the biology in his compost extract, “sending out the biology with a lunch box”.

The benefits of the use of these nutrient extracts coupled with the regular monitoring Sergio’s is performing is shown through the brix level of his vines. The first year he started applying nutrition more seriously the brix of his vines measured at 4-6%, and has increased to a brix level of 17-21% measured just before last year’s harvest. Considering the ideal brix level for healthy and resilient vines is 12%, this is truly an incredible result for Sergio!


Pictures of Johnson-Su reactors being built at Sergio’s vineyard – made from shredded wood, sheep dung and waste green matter collected from the vineyard

Finally, Sergio discusses how transitioning to these regenerative practices has affected his vineyards finances. During the three years of organic conversion Sergio did not experience any improvements financially, as while he was spending less on inputs he also experienced a reduction in yield from weaning his vines off of relying on chemical fertilisers, and through his conversion to a vine species that produces less but higher quality fruit. However, now out of his conversion period Sergio is able to sell his grapes at three times the price and is now producing his own wine, adding value to his business. These changes in management practices have decreased his cost of production and increased his economic return.  

It was great to catch up with Sergio and discuss his practical and innovative approach to vineyard management. If you want to learn more about how Sergio implements these regenerative practices in his vineyard, listen to the full conversation in the video below!

All of the beautiful images in this blog were taken from Sergio’s Instagram account – follow him at @sergio.grapegrower for more insights.

Regenerative Viticulture Insights: Exploring the beauty of native architecture in vineyards, with Mimi Casteel

Regenerative Viticulture Insights: Exploring the beauty of native architecture in vineyards, with Mimi Casteel 1080 1080 Sectormentor

Regenerative Viticulture Insights:
Exploring the beauty of native architecture in vineyards, with Mimi Casteel

We recently shared three amazing discussions from our second edition of the Regenerative Viticulture Series.

To celebrate our learnings, we’re releasing a roundup of each of the sessions and some of our favourite insights from them. In this first instalment, we’ve pulled together some highlights from our conversation with the brilliant Mimi Casteel, vineyard manager & winemaker at Hope Well Wine, Oregon.

Mimi grew up working on her parents vineyard and winery, where she first fell in love with the surrounding forests, going on to study a masters in forest science, and working as a botanist and ecologist for the US Forest Service.

In 2005 Mimi came back to farming and viticulture out of a desire to help make changes on private land, where she felt the true threats to the US native ecosystems were occurring. In 2021 she downsized to a smaller plot of land, meaning she no longer sells grapes, and has the opportunity to work more with practitioners looking to start on a regenerative path. 

Mimi is a trustee of The Regenerative Viticulture Foundation, a global non-profit aiming to support a transition to more agro-ecological practices in wine-growing, which enhance soil health and biodiversity. The foundation works to connect practitioners to existing educational resources and organisations that provide advice on how to enact this transition to regenerative viticulture.

“Everybody meets significant challenges and barriers on the path to doing a better job with the land. Our lands have been very under-served – so on the path back to health and resilience there are going to be challenges. Connecting people with that community of support to be able to keep going and try new things is critical work and I am excited to be a part of it.”

Moving away from producing grapes commercially and growing only for her own wine also gave Mimi the freedom to experiment with different regenerative practices herself; exploring how restoring and enhancing natural systems can support nature recovery and develop character in the wine. 

“I’m very excited to not only be starting again at a new baseline but also to be able to lift my own baseline curiosity in terms of what doing things differently can do for the wine itself and for the vineyard – bringing back together an ecology and geometry of an ecosystem – I would love to see where that takes the wine”

Mimi’s background in forestry has given her a unique approach to viticulture and has influenced her management decisions in interesting ways. She has a particular focus on the different dimensions in a vineyard, exploring how encouraging a wider range of natural architecture, such as shrubs and trees, can benefit the farm ecosystem both above and below ground, much like the varying layers of habitat within a forest.


                                      View of large natural architecture surrounding Mimi’s vineyard


Mimi gives the land space to develop naturally while assisting through management and replanting

In the first year at the new site, Mimi allowed herself the space to just observe what was happening on the land – noting what native seedlings were emerging, where, and allowing them to grow. 

This year she is looking to install some more wildlife architecture, particularly around the edges to add structural diversity alongside providing wind buffers, wildlife cover, food and forage. Aiming to create a “multidimensional geometry of symbiosis” through using native shrubs and trees to vary root structures with perennial grasses. Mimi is interested in how these different levels of architecture can reduce a farming system’s dependency on outside inputs to protect the crops that are being grown.

“I’m really trying to explore where the intersections are between what the vine needs, and what the ecosystem provides and also needs.”


                    Pictures of wildlife found at Hope Well vineyard taken from Mimi’s Instagram account

One major benefit of introducing large ecological features such as trees is the effect that their root systems will have on the underground network. In the first decade of its life, a tree will put all of its photosynthetic energy into its root system, and it is that root architecture which often determines the depths of the water table.

“I think we maybe underestimate what having trees in a system can do for water storage and water banking, but you can’t replace that fracking root structure with anything else we might put into a vineyard system. Even our vines now are very limited in terms of what layers of soil they are really exploring with their roots.”

This not only affects the resilience of your vineyard but has the capacity to contribute towards drought resilience on a regional basis. 

Mimi believes in starting with the “biggest architectural features that you want to bring back” and then “dialling in the details after that”. “You need a big base to have a tall pyramid!” – through her experiments over the years she has found that “you can’t spend too much time building the base of that pyramid – the bigger it is, and the stronger it is the higher you can go with whatever else you want to do”.  This is also important for minimising the potential for competition between this larger architecture and our vines. 

“There is a competitive discussion to be had – I don’t deny that especially at different stages of succession you will have competitive forces at play as the system comes into a homeostasis, as you will. That’s why I like to start by putting in those deep rooting perennials because as they grow, the capacity for a cooperative environment grows.”


Mimi goes on to explain how the development of the lower levels of architecture within the vineyard ecosystem and their role in managing disease

Disease pressure is a limitation for most viticulturalists. At Hope Well they have very wet springs and winters, creating significant powdery mildew pressure.

Mimi is exploring combatting powdery mildew without using chemical fungicides. She has found that the vineyard floor affects the humidity of the fruiting zone and the amount of water available at each point in the growing season. Cover crops will provide a buffer in the event of heavy rainfall late in the season. If cover is established it will absorb the water in place of the vines, reducing the likelihood of “blowing up” the fruit due to excess water uptake, reducing the risk of botrytis. Mimi has also been experimenting with cover crops under the vine itself; observing how the vines respond, how long the flowering period is and when they start to senesce, especially during the grapes ripening stage. 

In Mimi’s experience, vineyards are most vulnerable to fungal diseases when vines are growing the fastest. She likens the beginning of the growing season to when you clear cut a forest – there is an abundance of nutrients and moisture and the plants are eager to grow and grow quickly, resulting in large, water swollen cells that lack a certain level of structural integrity. Mimi therefore prefers less internode growth during this period, instead encouraging growth of small, lipid dense cell membranes to hopefully result in a higher density of nutrients and photosynthetic products staying within the cells, to increase the vines’ resilience against disease. Cover crops can help manage this period of extensive vegetative growth by absorbing some of the resources that would otherwise be used by the vines. 


Cover crops planted in the alleys between vine rows at Hope Well vineyard – taken from Mimi’s Instagram account


We also discussed the use of tillage within a vineyard and its effect on soil health & temperature.

Mimi’s region in Oregon tends towards an arid climate in summer, susceptible to drought, such as during the 2021 “heat dome” where temperatures were regularly recorded at over 46 degrees celcius. During this period Mimi measured the soil temperature on her own (un-tilled) land, compared with the soil temperature on a neighbour’s tilled fields. She found that her soils were as much as 15 degrees (Celcius) cooler than the tilled soils, a difference which affects drought resilience as well as the biological life the soil is able to support. 

Mimi also discovered that the vine canopies were degrees cooler in her vineyard, due to the presence of cover crops holding water in the soil, and enabling transpiration to occur. She also found that her cover crops were reducing the likelihood of frost damage during the winter – the covers held heat within the soil, so they stayed warmer for longer, and were not affected by frost until much later into the winter season. 

Mimi’s incredible findings represent powerful examples of the benefits of continual cover and living roots within the soil.


Finally, Mimi shared her advice on opening up practitioners’ minds to new regenerative concepts

While many ecological and economic benefits of using regenerative practices in vineyards are clear, we appreciate it can still be daunting to begin the transition. We asked Mimi how she began her transition and what advice she would give to others taking their first steps on a regenerative journey:

“Observation is key – that you try new things and allow yourself to be curious. Whether you are heading out to count earthworms or noting new flora growth between your vines, the main point is that you’re paying attention – It is also very beneficial to have a way of organising your observations and making a routine of it because you will notice other things as you go.”

“The most powerful driver for opening minds is having some repeatable observable feature to point to – encouraging people to adopt methodologies of recording their information through technologies like Sectormentor. Just having data to put in front of people is a very powerful stimulator for curiosity.”

“If wines are these time capsules of energy, the more we put into a system the more that is going to show up in the wine – make the wine and it will convince people.”

We loved having the opportunity to talk with Mimi who has inspired us to look at viticulture and a vineyards ecosystem from a new perspective. If you want to learn more about Mimi’s regenerative journey listen to the full conversation in the video below!

All of the beautiful images in this blog were taken from Mimi’s website and Instagram account @mimicasteel – check them out to learn more about Mimi’s philosophy at Hope Well.

Mary Retallack & Abby Rose – The Regenerative Viticulture Series

Mary Retallack & Abby Rose – The Regenerative Viticulture Series 913 1200 Sectormentor

The Regenerative Viticulture Series

Mary Retallack in conversation with Abby Rose

The Regenerative Viticulture Series has returned! We’re bringing new conversations with brilliant viticulturists, to discuss regenerative experiments on the vines – successes, failures & learnings along the way.

We’re excited to share our third conversation from the new season with the amazing Mary Retallack (@retallackviti on instagram). Mary is an agro-ecologist with many years of experience working & applying an ecological approach to viticulture, with a particular interest in native insectary plants and their potential in biocontrol. Mary runs her own small vineyard and consultancy Retallack viticulture Pty Ltd whilst also creating and running the phenomenal Ecovineyards programme, bringing native ground covers, soil health and an agro-ecological approach to vineyards across Australia.

The Regenerative Viticulture Series are a series of conversations hosted by Vidacycle with the aim of sharing the latest experimental thinking in building diversity, resilience & soil health on vineyard land.

At Vidacycle, we create simple tools for farmers & vineyards, focusing on the importance of observation to support regenerative practices – Sectormentor is our regenerative viticulture app!

Sérgio Nicolau & Abby Rose – The Regenerative Viticulture Series

Sérgio Nicolau & Abby Rose – The Regenerative Viticulture Series 1022 1069 Sectormentor

The Regenerative Viticulture Series

Sérgio Nicolau in conversation with Abby Rose

The Regenerative Viticulture Series has returned! We’ve collaborated with the Regenerative Viticulture Foundation to bring two new conversations with brilliant viticulturists, to discuss regenerative experiments on the vines – successes, failures & learnings along the way.

We’re excited to share another conversation from the new season – the brilliant Sérgio Nicolau (@Sergio.grapegrower on instagram), fifth generation regenerative viticulturist and agronomist in Portugal. Sérgio has turned his family’s vineyard from conventional to organic, and in the last few years transitioned to fully regenerative. He has had great success with his cover cropping to improve water retention, and makes his own fungal-rich compost and fish hydrolysate to improve the health of his vines as well as effectively using sap testing throughout the growing season to maximise photosynthesis and remove pest pressure. Sérgio is one part of Orgo – a group of 4 practitioners supporting others in their regenerative transitions.

The Regenerative Viticulture Series are a series of conversations hosted by Vidacycle in collaboration with the Regenerative Viticulture Foundation, with the aim of sharing the latest experimental thinking in building diversity, resilience & soil health on vineyard land.

At Vidacycle, we create simple tools for farmers & vineyards, supporting the use of observation to support regenerative practices – Sectormentor is the regenerative viticulture app!

The Regenerative Viticulture Foundation are a global non-profit organisation bringing together producers, scientists, educators, agricultural advisors and environmental organisations to share learnings and build up the data and resources required to enable viticulturists to make the transition from conventional or organic to a more biodiverse viticulture.

Mimi Casteel & Abby Rose – The Regenerative Viticulture Series

Mimi Casteel & Abby Rose – The Regenerative Viticulture Series 600 600 Sectormentor

The Regenerative Viticulture Series

Mimi Casteel in conversation with Abby Rose

The Regenerative Viticulture Series has returned! We’ve collaborated with the Regenerative Viticulture Foundation to bring two new conversations with brilliant viticulturists, to discuss regenerative experiments on the vines – successes, failures & learnings along the way.

We’re excited to share the first conversation of the new season – the brilliant Mimi Casteel, vineyard manager & winemaker at Hope Well Wine in Oregon. Mimi grew up working on the vineyard and winery of her parents, Bethel Heights Vineyard. She studied forest science & worked as a botanist and ecologist for the US Forest Service, giving her a broad ecosystem perspective when working with viticulture. Mimi’s experiments at Hope Well are rooted in creating beautifully regenerative, biodiverse & resilient ecosystems with the vines.

The Regenerative Viticulture Series are a series of conversations hosted by Vidacycle in collaboration with the Regenerative Viticulture Foundation, with the aim of sharing the latest experimental thinking in building diversity, resilience & soil health on vineyard land.

At Vidacycle, we create simple tools for farmers & vineyards, supporting the use of observation to support regenerative practices – Sectormentor is the regenerative viticulture app!

The Regenerative Viticulture Foundation are a global non-profit organisation bringing together producers, scientists, educators, agricultural advisors and environmental organisations to share learnings and build up the data and resources required to enable viticulturists to make the transition from conventional or organic to a more biodiverse viticulture.