AgriSea Shared Soil Story · Kaikohe, Northland

Patchy Grass to Peak Production:
The Van Oorschot Turnaround

When Stefan Van Oorschot and his parents took on what he describes as the worst farm in New Zealand, they had patchy grass, sinking mud, and cows that needed constant intervention. A few seasons later – with seaweed products, regrassing and surface drainage – they are milking fewer cows and producing 58% more milk solids, with an SCC below 230,000 and no antibiotic dry cow therapy.

80ha Dairy – Kaikohe, Northland+58% Milk SolidsNo Antibiotic DCTSCC Below 230,000

+58%

More milk solids – 12 fewer cows

<230k

SCC – no antibiotic DCT

4×/season

Soil and Pasture Nutrition via Tow & Fert

80 ha

Covered across the whole farm

CUSTOMER STORY – STEFAN VAN OORSCHOT, KAIKOHE

Starting from Scratch on the Worst Farm in New Zealand

Stefan Van Oorschot's parents, Pierce and Priscilla, bought the farm just 10 minutes west of Kaikohe in Northland in 2018. It was in rough shape. Stefan manages it day-to-day, with Pierce involved where he can and Priscilla working off the farm.

Stefan had been dairy farming when he first left school, but for his father's health the family moved closer to Auckland, where he spent 15 years in sheep and beef and on shearing gangs. Pierce had always said dairying was better – so they launched into buying the Northland farm. What they found when they arrived tested that conviction.

"Everything was pretty buggered. The grass was patchy and the mud stunk. We'd put cows in a paddock and come back in 30 days, and the grass wouldn't have grown back. It was described as an 'alternative' pasture, but really it was just flat weeds."

– Stefan Van Oorschot

Stefan Van Oorschot

Farm manager – day-to-day

Pierce & Priscilla

Parents – owners

80 Eff. Ha

Kaikohe, Northland

Bought 2018

Run-down – steady rebuild

The Numbers Tell the Story

In their first season the farm produced 190,000 kilograms of milk solids with 100 cows. In the 2024–2025 season, with 12 fewer cows, they produced over 300,000 – while keeping their SCC below 230,000, all without antibiotic dry cow therapy. The farm and the cows are in a completely different place.

First Season

190,000

kg milk solids – 100 cows – heavy reliance on imported feed

Recent Season

300,000+

kg milk solids – 88 cows – SCC below 230,000 – no antibiotic DCT

+58% more milk solids – 12 fewer cows

Then – First Season

•Patchy grass, flat weeds, "alternative pasture"

•Mud that sank the quad at the gateway

•Grass not recovering after 30 days

•Heavy reliance on imported feed

•Nearly every calving required assistance

Now

✓Grass like carpet – great coverage, growing well

✓Can drive the whole farm without getting stuck – even in winter

✓Cows healthy and in great condition

✓Calvings hands-off – no assistance needed

✓SCC below 230,000 – no antibiotic DCT

"The farm and the cows are healthier. The grass is like carpet now, we've got great coverage, and it grows well. In our first season, I had to assist nearly every calving, but now it's all pretty hands-off!"

– Stefan Van Oorschot

How the Turnaround Happened

The transformation came through three key steps working together: extensive regrassing, adding surface drainage with a drain spinner, and switching to seaweed-based products. Stefan is clear that the combination is what made the difference – and the seaweed products have been a consistent part of the programme throughout.

Seaweed Products Through the Tow & Fert

Stefan applies Soil and Pasture Nutrition through the Tow and Fert about four times per season, covering nearly the entire 80ha each time. He also adds a bit of dolomite to the mix and finds the application simple and effective.

Soil Holds Water When It Needs It – and Lets It Go

The soil water management has been one of the most dramatic changes. Stefan can now drive around the entire farm without getting stuck, even in winter – a striking contrast to the quad sinking at the gateway when they first arrived.

Regrassing to Mohaka Hybrid

Most of the pasture is now Mohaka hybrid ryegrass, which suits the Northland conditions far better than the "alternative pasture" they inherited. Stefan has also dabbled in chicory and plantain as part of the broader pasture improvement programme.

Surface Drainage with a Drain Spinner

Adding surface drains was part of the structural fix that allowed the other changes to work. Better drainage combined with the improved soil water retention from the seaweed programme has transformed what was once a muddy, waterlogged farm.

"The label on the seaweed products is pretty much true. The soil holds water when it needs it and lets it go when it doesn't. It's a massive difference. We can drive around the whole farm without getting stuck, even in winter. I don't know where the mud has gone."

– Stefan Van Oorschot

Product Used

Soil & Pasture Nutrition

Applied 4× per season via Tow & Fert – covers full 80ha

Combined With

Dolomite

Added to the Tow & Fert mix alongside seaweed

One More Thing – the Cows Notice It Too

Beyond the production numbers and the pasture improvement, Stefan has noticed something simpler: when he applies seaweed to the paddocks, the cows eat everything. It's an observation that resonates with farmers who understand that animal appetite is one of the most honest signals of feed quality.

"They'll eat everything when I spray seaweed on it. And the farm has a good population of dung beetles."

– Stefan Van Oorschot

Cows Eat Everything After Application

Increased palatability after seaweed application means better pasture utilisation and less wastage – a small but practical benefit that adds up across multiple grazings over a full season.

Dung Beetle Population

A healthy dung beetle population is one of the clearest indicators of a biologically active soil. Stefan notes the farm has a good population – consistent with the improved soil health the seaweed programme has helped build.

Stefan's Advice to Other Farmers

Having been through the transition himself, Stefan has straightforward advice for farmers considering making the shift to seaweed-based products – particularly those coming from a high-nitrogen conventional system.

Two Things Worth Knowing Before You Start

Reduce Nitrogen Slowly – Not All at Once

If you're currently using a lot of nitrogen, make the shift gradually rather than cutting it all in one go. The soil needs time to build the biology that replaces what synthetic nitrogen was providing.

Stick With It – The Results Are Worth the Wait

The biggest gains don't come in the first season. Stefan's 58% milk solid increase is the product of consistent application and patience over several seasons – not a quick fix.

As the quad sank into the gateway mud, I wondered if we'd made a mistake buying what I was sure was the worst farm in New Zealand. Now I can run a Tow and Fert over the whole farm with ease, any time of the season.

Stefan's a fan of the seaweed products and the prompt service from AgriSea. His advice? If you're using a lot of nitrogen, make the shift slowly – and most importantly, stick with it. The results are worth the wait.

See What AgriSea Can Do for Your Farm

From run-down Northland dairy to peak production – talk to your local AgriSea Field Consultant about building a programme suited to your soil, your system and your long-term goals.

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