Stream restoration in Ashburton

The work began with a practical need: keeping stock out of waterways and dealing with wet, unproductive patches. Over time, those first steps grew into a long-term stream restoration and biodiversity project, shaped by trial and error, ongoing maintenance and a growing pride in what the planted areas were becoming.

Starting with areas that need the most attention

When the farm was first purchased, parts of the stream corridor and surrounding wet areas were covered in gorse and broom. Several small creeks and springs also ran through paddocks, and one wet area became increasingly boggy as water levels recovered. Cows regularly pushed into the area, damaging the paddock and making it harder to manage. Fencing these waterways was the first practical step, but it also opened the door to thinking differently about what these parts of the farm could become.

A practical, long-term approach

The work did not happen all at once. After getting established financially, Mark and Wendy began planting along the stream and around wet corners, learning as they went. A boggy paddock area was reshaped into a pond, then fenced and planted. From there, the planting expanded over time to include stream margins, side creeks, wetland edges and shelter areas. Species have included flax, kōwhai, tōtara, pittosporums, ribbonwood, beech, sedges and other natives suited to different parts of the site.

Like many successful planting projects, the approach evolved over time. Early lessons showed the importance of protecting young plants, staying on top of weed control and planning for ongoing maintenance. The planting strategy shifted towards establishing cover first, then adding longer-term canopy species later. The result is a more resilient and increasingly self-sustaining planted area, with self-seeded seedlings transferred to new areas and some seed now being collected and propagated on-farm for future planting.

Benefits of stream restoration

• Shading from established planting has reduced aquatic weed growth in the stream, cutting the need for repeated in-stream clearing.
• Wet and unproductive areas are now managed as biodiversity features rather than ongoing problem paddocks.
• Planting has improved the visual appeal and feel of the farm, making it a more enjoyable place to work.
• Waterways are home to long fin eels and rare Canterbury galaxiids, while native bird life and bird song has increased.
• Propagation from on-farm plants is helping reduce the cost of future planting and build long-term momentum.

How did they do it?

Mark and Wendy started planting along the stream and in wet areas, learning by doing rather than following a strict master plan. Early on, a retired farmer with native-planting experience helped select plants for one area (a roadside/dust-driven shelter planting), but since then the approach has been self-directed—reading, observing what works, and adapting over time.

A key early project was reshaping a boggy wet patch into a pond, using a digger for form the area before fencing and planting it. From there, the work grew gradually across the farm, with planting added along stream margins, side creeks, wetland edges, and shelter areas.

A wide mix of native species has been used, including flax, pittosporums (including compact varieties), kōwhai, tōtara, beech, ribbonwood, mānuka (trialled) sedges and carex. As the planted areas became more established, groundcovers and ferns were added to help fill out the understorey.

Challenges along the way

Establishment has taken time and consistency. Weed control is critical in the first few years, and missing maintenance can quickly set plants back. Frost, browsing pests such as hares, and occasional stock break-ins have also caused losses. These setbacks reinforced the need to protect planting investment and keep the scale of work manageable.

What’s next

The next stage of work includes continuing planting around the stopbank and wet edges, infill planting (particularly larger trees), improving pest control, and expanding monitoring across the farm’s waterways. It is a good example of how biodiversity work can sit alongside a productive dairy system, with practical gains for the farm and long-term benefits for the wider environment.