2024 Vineyard Report

Tinja’s Regenerative Techniques & Trials

Cover Crop and Crash Grazing Sheep

This is a technique we’ve been using for a few years now and is a fundamental piece in the Regen Ag toolkit.

In early autumn, we sow a multi-species cover crop between the vines.  From early Winter, once the vines drop their leaves, we move our sheep through the vineyard block by block to graze down the cover crop and any other voluntary weeds (think free mowing service!). As they do this, they fertilise with their manure and simultaneously trample down the cover crop into the soil which helps the plant material break down and feed the soil.

A cover crop is a mix of beneficial plants that we sow between the vines to increase biodiversity, add nutrients, and slowly increase the organic matter levels in the soil.

By using a cover crop to feed the soil, we help foster a relationship between the vines and the soil micro-organisms, which in turn helps the vines to be naturally more resilient and have an easier time recovering from extreme heat, drought, and disease.

This year we will include perennial native grasses into our cover crop mix. Native grasses provide habitat for vineyard predators, are drought and frost-tolerant, and suppress weeds that would otherwise compete with the vines. Over time, these grasses will provide 100% permanent ground cover.

By using cover crops and sheep grazing, we’ve seen an increase in the soil’s water-holding capacity. Far fewer weeds come up each year and the weeds that do grow are less competitive with the vines, and are softer and easier to remove under vine. All these practices also mean less tractor time, which means less diesel used and less compaction of the ground. Ultimately, the less tractor time in the vineyard the better– for the vines and the planet.

Annual Compost Application of Biodynamic Compost

This is another important way that we increase soil organic matter over time in the vineyard and is a crucial part of our biodynamic practice.

We put out compost in winter at a rate of 4 tonnes/ha. The compost is made from waste products from all over the property like food scraps from the kitchens, cardboard from the cellar door, and garden waste from the market garden. We add the biodynamic compost preps to each new heap, and the compost usually takes around 3-6 months to break down before we can use it.

By increasing soil organic matter by 1%, we can hold an additional 170,000L of water in the ground! This not only helps us save resources by reducing the need for irrigation, but also means less run-off and more infiltration of water when it rains.

Undervine Ground Cover Trial

Going No-Till on the farm comes with its challenges, mainly ‘how do we eliminate competitive weeds without disturbing the soil?’ Chemical herbicides are not an option in an organic system, so we have to get creative. This inspired Kesh to set up trials looking at under-vine ground covers, and these results have informed our vineyard’s No-Till (permanent ground cover) Strategy.

Before we get into the trial, let’s start with ‘What does No-Till Mean”? Tilling is a common vineyard practice where a tractor armed with a rotary hoe runs between the vine rows to break up the soil. It is a common belief that tilling the soil helps to reduce compaction and weed competition. While this may be true in the short term, in the long term tilling can actually negatively impact the health of the vineyard.

Kesh explains that breaking up the soil is the equivalent of a giant bulldozer tearing through a city. It destroys not only the parks and lawns but also the homes and buildings that give us safety to live and grow. It’s the same with the soil microbes. They create a complex network below the ground and by tilling the soil, we destroy their homes, roads, and access to resources. Without this network, the microbes die off or move on, leaving the vines completely reliant on us for all their needs.
Living soil full of a diversity of microbes is integral to the overall health and resilience of the vineyard. Not only do the microbes synthesise nutrients for the vines, but they also help to protect the vines against disease and pest attacks. Tillage also destroys soil structure, by destroying the biotic glue that holds the soil particles together and killing the microbes that produce this glue. This glue gives soil it’s fluffy texture and helps hold moisture in the ground to avoid erosion, run-off, and compaction.

Bare ground leaves soil exposed to the sun and more water loss from evaporation. When you cover the soil it’s able to hold more moisture, lower the soil temperature (which creates a happier environment for vines and microbes), and sequester carbon from the atmosphere. All huge wins!

To truly be No-Till, we must eliminate tillage in the under-vine area as well. This is easier said than done, as weeds growing in this area compete directly with the vines for water and nutrients, and grow tall into the canopy restricting airflow which adds to disease pressure.

We’ve seen huge success using cover crops in between the vines, so Kesh wanted to test how we could use them under the vines too and eliminate tilling. To do this, we need to find an alternate solution to managing weeds that grow directly under the vines. To keep this area covered and weed-free, our options were mulch (expensive and requires constant work to maintain) or ground cover (plants) that don’t compete with the grape vines.

From late 2022 to 2023 Kesh tested 3 ground cover options:
1. Creeping saltbush: established well, with no irrigation.
2. Dichondra: very slow to establish with no irrigation. Grew slowly in little clumps, but eventually spread. In phase 2 we introduced it into the Nero d’Avola block where we have irrigation and we saw more success.
3. Clover: struggled to germinate in our trial.

Over a year and a half, it has become clear that by using creeping saltbush and dichondra – both native Australian ground cover plants – we can utilize permanent ground cover in the vineyard to eliminate tilling and increase the overall health of the soil and vines.

Biological ferments

The second trial Kesh is working on investigates Natural Farming Systems to produce biological ferments (made from ‘waste products’ around the farm) that can be used as an alternative to copper and sulphur for disease protection, as well as foliar feed the vines with nutrients at the same time.

Copper and Sulphur are both commonly used in vineyards to fight off downy mildew and powdery mildew, respectively. While these are both organically certified products, we’re always trying to reduce the inputs that we need to buy and bring onto Tinja. Rather, we aim to achieve a holistic approach to treating the vines using things we grow right here on the property.

These ferments are made by adding waste products to rainwater and using indigenous micro-organisms in the form of leaf mould to break it down into a ‘tea’ of microbes and nutrients.
This tea can then be sprayed onto the leaves, where the microbes colonize and protect the leaf surface by occupying all the available space and preventing pathogens from taking hold.

Rather than using a pre-bought fertilizer that only addresses a few pieces of the puzzle, these ferments are a perfectly balanced nutrient source for the vines and can be customized to support the vines at each growth stage.

For waste, she collected plant materials discarded from the Zin House gardens, nettle, and vine leaves that were previously cut during de-suckering. For her indigenous microbes, she collected leaf mould growing under trees around the property, which has a diverse collection of microorganisms adapted to grow and thrive on Tinja.

The trial is ongoing, and Kesh has already made some amazing observations! The ferments did provide the vines with nutrients which helped them become stronger from the inside out. This increase in health made the vines less susceptible to pest and disease attacks, and the microbes seemed to provide an added layer of protection for about a week after application.

While this doesn’t fully replace our use of copper and sulphur, it means we can begin to reduce our use across the vineyard, slowly. Our goal is to always keep improving.

As you can see, the vineyard team has been incredibly busy this past year. With a strong strategy for 2024, we have confidence this will be one of our best and most sustainable growing seasons yet.

Stay tuned for more!