Cole Groves

The farm has a mix of light and heavy soils. In the 2019/20 season they peak milked 435 cows, and in 2020/21 they are adjusting this to 415 cows, focusing on reducing N fertiliser and N in feed, and utilising autumn fodder beet.

"Ultimately, we wanted to make sure our business and farm was going to be able to operate into the future with the environmental limits coming into effect in the next 5, 10, 15 years. In our mind we needed to make changes now so that our farm system has time to adjust, so we needed to be proactive. Through the project, using our farm consultant, Farmax and Overseer we are focusing on reducing our environmental footprint while maintaining sustainable profitability." - Cole Groves, Groves Dairies - Coldstream Pastures

Farm Information

Mitigations Implemented to Date

Increasing Clover Content

Clover content one year on from broadcasting.

Last season Cole identified a paddock that had particularly low clover content, and with the need to reduce synthetic N he wanted to make sure they were maximising clover for N fixation. The pasture was relatively new, and so he decided to try broadcasting some clover seed in February 2020 to introduce the clover back into the sward.

“We used a mag spreader and did a lot of trips up and down the paddock to broadcast it, as the seed is small and doesn’t go any further than you can throw it. We then grazed it with the cows and followed with a harrow and a roller. We’ve been really pleased with the result, and the clover content the summer following has exceeded our expectations.”

Fertiliser N Use

“We are looking to reduce our synthetic nitrogen fertiliser use in preparation for the 2021/22 season limit,” says Cole. “For the 2019/20 season we applied an average of 260 kg N fertiliser/ effective ha, and we are looking to reduce to an average of  220 kg N fertiliser / effective ha for the 2020/21 season. To do this we are targeting reducing early spring and late autumn applications, reducing the amount we apply each round during the middle of the season, and looking to remove the January application since clover should be more active then.”

Irrigation Infrastructure

Cole and Virginia have improved their irrigation infrastructure and therefore irrigation efficiency by replacing a small area (1.1 ha) of border dyke with fixed grid irrigation. This will allow more accurate irrigation, reduce drainage and therefore N loss from the root zone in this area. Up until now, the farm was unable to achieve higher than a B in their Farm Environment Plan audit because they had an area under border dyke irrigation. Cole is also planning to add solenoids to some of their k-line taps – this would give them the ability to turn on specific k-lines for a set number of hours to apply an appropriate amount for the conditions, and reduce drainage.

Irrigation testing

 ”Bucket testing our irrigation is something we routinely do each year, to check that we are applying what we think we are,” says Cole. “We’ve found the fixed grid difficult to do accurately, as our system is set up to only run one sprinkler at a time - so to test a certain area becomes tricky with turning various sprinklers on and off.”

Stocking Rate and Feed System

Cole and Virginia are reducing their stocking rate in 2020/21 on their milking platform, from 435 peak cows in 2019/20 down to 415 for 2020/21 (4.1 to 3.9 cows/ha). They will reduce imported feed from 935 kgDM/cow to 749 kgDM/cow.

In addition for 2020/21, 4.5 ha of fodder beet will be grown on platform for the first time this season for autumn supplement, with this estimated to contribute an additional 267 kgDM/cow as home grown crop.

Cole's Top Tips

"Consider all options, and don’t write crazy ideas off. We have always modelled our farm system, so combining Farmax and Overseer has had huge benefits for trying to find that ’sweet spot‘ for our smaller farm. Having our consultant qualified in Overseer is also paying huge dividends in being able to model ideas quickly and efficiently."

N loss Progress

First Year on Farm: 2017/18: 90 kgN/ha/yr (OS v6.3.4)
Year End: 2019/20: 75 kg N/ha/yr (OS v6.3.4)

As a member of MHV Water, the farm does not need to meet an individual reduction from a baseline, as the consent for this is held by the irrigation scheme collectively.

The Groves are one of 50 farms who are partnering with the DairyNZ funded Selwyn/Hinds – Meeting a Sustainable Future Project. They are exploring the options for reducing their farm’s environmental footprint (water quality and greenhouse gases) while maintaining profitability and considering the strategic objectives of their business. As part of the project, these 50 farms are sharing a range of ideas, learnings, case studies and analyses as the project progresses.