Tech to give avocado farm an edge

June 25, 2020 | 5 Min read
Alterra is setting up its first avocado site using technology to enhance sustainability and yield.

Change is expensive and can be difficult for farming businesses, but agricultural land developer Alterra is starting from scratch and building best practice into its foundations, literally from the ground up.

Brett Heather, Chief Operating and Technical Officer at Alterra, says the company is not reinventing the wheel as it introduces technologies to control water and nutrient delivery which impact fruit quality and shelf life with the consumer — something it can plan for well before any trees are planted.

“Change is pretty scary when you’re deviating from what everyone is doing out there, but it’s really taking a collection of best practice tools across the horticultural industry and applying them to what we are doing,” he told Stockhead.

“We’re adopting some common-sense approaches to farming that optimise what we’re doing. It’s not a revolution; it’s a grass roots, common-sense approach.”

Heather expects that adopting best available farming practices will enable Alterra’s avocado developments to be sustainable, high yielding, and help to mitigate the rising threat of climate change.

Starting from scratch

Alterra has a long history on the ASX as an ESG (environmental, social, governance) agricultural investor but pivoted into the high-growth, highly sought after avocado industry last year while retaining its sustainable creds.

Recently it closed a deal for the 300-hectare Carpenters project, which is located in the “golden triangle” agricultural region of Pemberton in south-west WA, this includes constructing a licensed dam site to hold over 3 gigalitres of water, which will be one of the largest private dams in Western Australia. “We are very lucky in that we are doing a greenfields development and starting from scratch,” Mr Heather said.

Alterra will install best practice irrigation and fertigation systems, which will ensure precious resources of water, nutrients and power are used in the most efficient way. This ensures the project delivers strong environment sustainability as well as financial performance.

Key to driving a strong bottom line of the project for Alterra is crop yield, fruit size and quality. These project metrics are intrinsically tied to irrigation and fertigation practices, this is a good example of where a strong financial performance (through system efficiencies) will deliver positive environmental outcomes.

The company is introducing an Israeli drip irrigation and fertigation (that’s the addition of nutrients, or fertiliser to irrigation) system, dendrometers to measure expansion and contraction in trees’ trunks and soil moisture probes.

The project will grow the Hass avocado variety which is in demand by consumers globally. This variety will be grafted utilising different root stocks that help resist soil borne diseases such as phytophthora and increase tree vigour.

Heather says their technical partners have also developed a number of tree canopy management processes to help improve fruit quality and quantity and Alterra will use these techniques in their project.

The technologies

Drip irrigation has been around for decades and was pioneered by Israeli farmers. Alterra is working with Israeli firm Netafim’s local team to test and install a system that delivers water and nutrients to the feeder roots of the trees in the top 30cm of the soil profile.

“Drip irrigation is said to be 20 per cent more efficient from a water perspective than micro sprinklers. Because irrigation pumps run on power it also means savings in electricity use too because of the lower water rate,” Mr Heather said.

Adding fertiliser to that system means growers can adjust exactly how much water and nutrients a plant is receiving at the different stages of the plants growth, from tree flowering to shoot growth to fruit growth. Heather says this has measurable consequences for consumers: for example fruit that has too high nitrogen to calcium ratios doesn’t last as long on the shelf and can lead to poor fruit quality with the consumer.

Netafim is now running trials with Alterra to see whether a larger or smaller drip irrigation rate is more appropriate for the Pemberton soils. This will ensure the project takes a strong scientific approach that is blended with a very practical implementation at the local project level in Pemberton.

“It’s not a revolution but there’s not that many examples in Western Australia of drip irrigation with avocados. There are more examples of East Coast orchardists doing this, and some innovative growers there have been using drip for the last 15-20 years, but there’s not a lot of them.

“Netafim pioneered drip irrigation in Israel and now has significant experience with drip irrigation of avocados all around the world. In Australia, Netafim has been involved with many large projects and Alterra is looking to draw on this experience to ensure the success of their project,” said Netafim WA Sales Manager Patrick Johnson.

Other critical technologies Mr Heather has sourced are soil moisture probes and EC probes that measure moisture and fertiliser at different levels of the soil profile.

They’re interested in the top 30cm, where avocado tree roots are most active and take most of their water and nutrients from. Not enough water in the top 30cm will stress the tree and potentially reduce the size of the fruit. Too much means water and nutrients will leach from the soil and in some cases can kill trees as avocados are very sensitive to overwatering.

Dendrometers are calipers that attach to the trunk of trees and measure how much it expands and contracts over time. Heather says readings from this can be taken as a sign of growth and stress and is another indication of a need for more or less water and fertiliser.

Canopy management is a fancy term for pruning and managing tree growth, with the intention of ensuring enough light gets through to lower branches to encourage more growth within the protected canopy of the tree.

A little help from our friends

Heather is the ringmaster overseeing the coordination of these ideas, but he says it’s the technical partners who are bringing a vast amount of knowledge.

Experienced avocado and citrus producer Richard Eckersley brought the drip irrigation idea to Alterra, along with Pablo Liguori a nationally renowned agronomist that Alterra engaged.

Second generation avocado growers William and Debra French, of French’s Group, are providing significant local experience and detailed canopy management expertise.

But as many investors will know, companies can overcapitalise in the search for best practice.

“This is all about keeping it real,” Heather said.

“Alterra have come in with a clever strategy of not being a corporate business that thinks it can show farmers how to do it. We’ve been able to tap into local grower expertise through our technical partnerships and get their insights on where to invest and where not to.

“We’re not gold plating the development, we’re making sure we build our assets with the right irrigation and the right fertigation to optimise our investment.”

Mr Heather says as more Australian avocados are exported they’ll need to compete with the powerhouse producers of South America and South Africa.

Australia has high labour costs, so technological and scientific approaches to lifting yield and producing avocados that travel well are where companies like Alterra have an edge.

“This game is really about the consumer. Too often we forget there’s a consumer at the end of the supply chain. What they want is a good eating experience time and time again,” he said. We want to ensure we can deliver this and become known for top quality avocados.

“Let’s build the system from the ground up so we can export fruit out of Australia.”

Currently Australia only exports around three per cent of the avocados that are grown nationally. This is a tiny fraction of what we grow and points to the significant potential to expand sales of locally grown fruit to overseas markets.

Australia has a free trade agreement in place that gives avocado growers direct access to Japan which is exciting for the country’s avocado industry.

While establishing a site that can compete with foreign-grown avocados, Mr Heather also has an eye on climate change.

He isn’t looking at average temperatures, rainfall, wind or frosts, but how to protect his orchards from extremes that are expected to become more frequent over the coming decades.

“Agriculture can be an unforgiving place. You’re exposed to mother nature and she can be quite unforgiving if you’re not prepared” he said.

“People talk about averages, but it’s not the averages in farming that get you, it’s the extreme heat or frost.” We know the climate is becoming hotter and dryer, fortunately Pemberton is in a cool mild climate, however, we are building the development to cope with changes in the coming decades.

Mr Heather expects that by adopting the best technology in use today — not the bleeding edge — Alterra will set up an avocado development that is not only more sustainable over time, but also competitive and protected from the vagaries of climate change.

Categories Avocado Technology in agriculture

Read also

View all

Cryogenics preserves genetic lines of avocado

Australian research results in higher yielding avocados

Avocados from WA access Japan via direct flights