Category Archives: Fertiliser

The Role of Soil Microbes in Soil Plant Interactions

Our latest podcast is now online. Phillip Schofield talks with Georgia about the role microbes play in soil plant interactions, the use of Visual Soil Assessment (VSA) and practical ways to improve soil health on-farm.

Phillip is a soil nutrition consultant based in Hawke’s Bay. He has a PhD in Plant Science from Massey University where he studied autotoxins, herbicide residues and pathogenic fungi in asparagus crops. He has many years’ experience in soil conservation, and nutrient management in the Hawke’s Bay area.

Our thanks to our loyal sponsors and to Radio Kidnappers for support with our podcast series.

Future Proofing Vegetable Production: Milestone 9

We continue to have solid engagement with our farming communities in Levin and Gisborne.  At this stage our project plan had us monitoring the effectiveness of a bioreactor to manage nitrogen leaving the field, but we have not been able to find a regular flow of nutrient rich water that we can treat. Further drain flow monitor through Levin has continued to show little nitrogen in the drains flowing past the cropping blocks so any nitrate losses are assumed to be via groundwater, possibly reappearing in the Arawahata Stream between the cropped areas and Lake Horowhenua.

We are working with growers to ensure that they are applying the correct rate of fertiliser in the right place so that they do not lose excess nutrients from the field.

As part of the suite of tools to help farmers, we have created LandWISE Nutrient Budget templates and updated the FertSpread web-calculator for broadcast spreader calibrations to include Fertplace for placement equipment such as planters and side-dressers.

The Nitrate Quick Test is a rapid measurement of available nitrate in the plants’ rootzone

The three main tools we are using in our work with growers are:

  • The LandWISE Nutrient Budget: used in the crop planning stage to ensure planned fertiliser practice follows industry good practice.
  • The Nitrate Quick Test soil test: used as an active management tool during the crop to check the fertiliser plan and to validate additional fertiliser applications where the grower expects that extra fertiliser is required on top of what was originally planned.
  • The calibration tools, FertSpread and FertPlace: used to ensure that the fertiliser application equipment is evenly applying the fertiliser at the target rate where it is required.

In the coming season we have started two large, replicated trials in Gisborne focusing on nitrogen application rates to tomato and sweetcorn crops. Late winter soil testing to 90cm has shown a large range of soil nitrate levels (60-257 kg N/ha) in paddocks across Gisborne. Planned nitrogen fertiliser applications across these blocks were the grower standard rate.

Further work we are completing is turning the LandWISE Nitrogen Budget template into an online app for growers to use. The aim is a mobile-friendly tool that growers can use in the field. By making the information available on the technology growers always have with them, they will be able to simply validate their planned fertiliser plan against industry good practice and make more informed fertiliser decisions.

For queries, contact us here

Many thanks to our project funders, and the growers and industry folk who are putting so much time and effort into being the best they can be.

 

Memberships Open for 2020-2021

Calling all followers and friends of LandWISE, we invite you to become a financial member this year.

Your support is vital for LandWISE to continue doing what we do. We rely on farmer support to ensure the backing of new projects, discover new areas for research or technology adoption, and to fund field days, workshops and the development of practical resources. 

LandWISE Membership is a great way to support the mission of sustainable production in New Zealand, and as a member you’ll benefit from:

  • Results from on-farm trials
  • Projects focussed on real farmer and grower problems
  • Regional field days and workshops on a range of topics from conserving soil to nutrient management and novel fertiliser technology
  • A discounted registration at the 2021 LandWISE Conference
  • Subscription to our annual LandWISE News publication

Membership is open to all who are interested in primary production and share our values. We hope you’ll consider becoming a member, or forward this on to a non-member if you already are!

Sign up here >

Reducing Nitrogen Losses from Intensive Vegetable Production – Panel Discussion

LandWISE: Promoting Sustainable Crop Production
LandWISE: Promoting Sustainable Crop Production
Reducing Nitrogen Losses from Intensive Vegetable Production - Panel Discussion
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Thank you to those who joined us for the Live Panel Discussion with June’s podcast guests. We were thrilled to get so many participants in our first live webcast, and appreciated the rich conversation as a result of the varied viewpoints from panel presenters and listeners.

For those of you who weren’t able to make it to the Live Panel on Reducing Nitrogen Losses from Intensive Vegetable Production we recorded the discussion and you can listen to it above.

The Panel Discussion was presented on June 30th, after our presenters each featured on the LandWISE Podcast. If you’re interested to hear more from Jay Clarke, Luke Posthuma, Georgia O’Brien or Charles (Merf) Merfield, you can listen to their podcast episodes here:

All Podcast Episodes here >

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Introducing our Podcast

Unable to gather for our popular annual conference in May, but not wanting to you to miss hearing new ideas about  sustainable production, we joined the virtual conference crowd.

We are pleased to present “LandWISE: Promoting Sustainable Crop Production” a podcast that will bring the insights of lead researchers, technologists, and farmers to listeners from all over the Ag and Hort industry. Each month has a theme with guests joining on the last Friday of the month as a discussion panel.

This month we’re presenting “Reducing Nitrogen Losses from Intensive Vegetable Cropping” starting with our first guest Jay Clarke, Director of Woodhaven Gardens.

Woodhaven was named the Regional Supreme Winner at the Horizons Ballance Farm Environment Awards in April 2020. We are looking forward to hearing how Jay and the Clarke family have transformed Woodhaven’s growing practices to achieve this outstanding recognition.

JUNE: Reducing Nitrogen Losses from Intensive Vegetable Cropping

 

Growers Making Changes (Jay Clarke – Woodhaven Gardens) Friday 5th June
On-Farm Trials with Growers (Luke Posthuma, LandWISE) Friday 5th June
A Grower-Friendly Nutrient Budget Template (Georgia O’Brien– LandWISE) Friday 12th June
Cover and Catch Cropping (Charles Merfield – BHU Future Farming Centre) Friday 19th June
LIVE PANEL DISCUSSION – send in your questions to info@landwise.org.nz Friday 26th June 1:00 pm
Listen to Podcasts online here >
Listen on Spotify >

On the last Friday of the month – look out for our live Panel Discussion where we bring together all of the guests from the show and ask them your questions.

Email us your questions to info@landwise.org.nz

Made possible by our conference sponsors:

LandWISE 2020 – CANCELLED

IMPORTANT ANNOUCEMENT: LANDWISE 2020
CANCELLED

WE HOPE TO BRING IT TO YOU IN A DIFFERENT FORMAT. WE ARE ACTIVELY EXPLORING OPTIONS AND OPPORTUNITIES

The COVID19 beat LandWISE 2020. We were looking forward to an interesting two days filled with presentations from lead researchers and growers, networking, and practical demonstrations focussed on the theme of “Back to the Future”. But that cannot happen.

We regret this, but fully support the government’s initiatives and a fully complying at work, home and play. All registration fees have been refunded. We are working with our loyal sponsors to find ways to bring you the ustainable cropping messages we had lined up.

LandWISE staff are still working, so contact us by email or phone.

Dan, John and the LandWISE team

Nitrate Management Demonstrations – Gisborne 4 Feb

We had a good turn out at our Nitrate Quick Test and Alternative Application Technology Demonstrations in Gisborne on  4th February. Many thanks to Calvin Gedye and family for hosting the event.

Intended for Growers, Agronomists, and Fertiliser Reps, it was a chance to show and see some new technologies and talk about trials we are running in Gisborne and Levin. Attendees saw  demonstrations of:

TeeJet fertiliser nozzle on left, Stream Bar on right

Managing plant available nitrogen in soil is critical to ensuring crop yield and quality targets are met, and the risk of losses is minimised. However Nitrate-N, the main source of N available to plants is highly variable spatially and over time. Regular soil testing can help growers make better decisions about fertiliser use. Quick-N tests are affordable, easy to use and can give results in less than half an hour.

Why liquid fertilisers? In order to sidedress N more frequently and match crop demand closely, application needs to be efficient, even and easy. Liquid fertiliser application technology is progressing, and many attachments are now available to fit spray booms, in a variety of different spread patterns. Specialised nozzles do not mist, but apply large droplets that run off leaves and minimise risk of burning.

The dropper systems apply liquid direct to the soil alongside the plants, where root activity is greatest.

Dropper systems apply liquid fertiliser direct to the soil. We are trying various types for different applications such as potatoes or sweetcorn

This workshop was presented as part of our SFF project Future Proofing Vegetable Production.

Nitrogen Management Field Day – Levin 23 Jan

Many thanks to Woodhaven Gardens for hosting the Nitrogen Management Field Day we ran in Levin with VegetablesNZ. Thanks also to Antony for bringing hard copies of the new good practice guidelines, “Nutrient Management for Vegetable Crops in New Zealand“.  

We began the day with Luke discussing soil sampling strategies to make sure samples are representative. This involves taking at least ten samples, more from large areas, and ensuring samples taken fairly represent the variation across the vegetable bed and across the whole block or paddock.

Luke leads discussion about soil sampling methods to get good results

Georgia presented the Quick Nitrate Test method and the kit that is avaiable to growers. We use the test frequently in our trials and to guide nitrogen fertiliser use at the MicroFarm. We find the shaking of soil in the test-tube is important if reliable results are to be obtained. You must allow the extract solution to access all the soil to release the nitrate.

Georgia presents the Quick Nitrate Test

Woodhaven agronomist, Karen talked about their experiences using the Quick N-Test. They paired the quick test with standard lab testing while they learned how results are affected by soil variations and soil moisture levels. They don’t take the exact quick test result numbers, but use them to guide adjustments to their fertiliser application rates.

We demonstrated three alternative methods for applying liquid fertilisers; TeeJet, Stream Bar and home made Y-Drops. We think liquid fertiliser can offer significant benefits by enabling easier splitting and more accurate applications and reducing the risk of leaching while helping maintain excellent crop nutrition.

Droppers split near ground level and apply streams of liquid fertiliser to the soil beside row crop plants. This type of application is an alternative to banding dry fertilisers

The Y-Drop system is suited to row crops such as corn, broccoli or other brassicas. It drags soft hoses along the plant rows applying a stream to either one or both sides, close to the plant where uptake is most efficient. 

TeeJet nozzles (left) and Stream Bar (right) apply streams of coarse droplets that tend to run of plants and avoid risk of burning foliage. These are alternatives to broadcasting dry fertiliser

The TeeJet and Stream Bar systems replace standard spray nozzles, given a curtain of droplets along the boom. The TeeJet has diverging streams so application spacing can vary if the boom rises or falls. The Stream Bar tends to maintain a more uniform application. These systems are alternatives for crops such as baby leaf, baby beetroot and lettuces where dry fertilisers would be broadcast.

This field day was part of our Future Proofing Vegetable Production project and was held with support of Woodhaven Gardens, Pescini Bros and Vegetables New Zealand along with our major Project Sponsors.

Spring and Summer Trials

Spring has been a busy season so far for LandWISE staff and our Growers. We have been actively working with 10 growers based in Levin and Gisborne as part of Future Proofing Vegetable Production to test a variety of alternative management practices – particularly around fertiliser planning and application(s).

In Levin, we have 4 trials on Spring Brassicas testing standard grower practice for fertiliser rate and application timings with “Good Practice” prescriptive fertiliser planning based on the Vegetable Guidelines by Morton and Reid (2019). As well as reducing total N rates these trials will also assist growers to use Quick Nitrate Test Strips, and develop their understanding of how Nitrate fluctuates in the soil profile and over the course of a crop growth cycle.

One grower will be hosting several trials on his potato crops in conjunction with a PhD student from Massey University. One of the trials will focus on using liquid dribble bar applicators fitted to a spray boom to apply nitrogen fertiliser as split side-dressings. Another trial will look into the potential for biological products to improve the mineral N supply from soil to the crop. The overall aim with this work is to reduce the risk of N leaching by minimising the amount of available N, particularly nitrate, that is in the soil profile at any one time, and at risk of loss.

Several trials are planned in sweetcorn, the first of which will investigate the potential for current rotations to provide adequate soil nitrogen with reduced rsates of N applied at side dressings. At present one of our Gisborne growers is growing sweetcorn following winter cover crops and peas in spring. They want to know if the sweetcorn crop yield could be maintained or improved with reduced fertiliser N additions due to the previous crops which already provide improved soil structure and organic matter.

Another sweetcorn trial in Gisborne will focus on Phosphate in starter fertilisers. At present most growers in the area are using P in their starter fert blend, despite having optimum or above optimum Olsen P values in the soil. This trial will test the impact of removing P from starter fertiliser, on a high fertility soil whilst maintaining other key inputs (e.g. sulfur, nitrogen).

Finally, in a tomatoes crop LandWISE will assist another grower to test their current starter fertiliser rate against reduced rates (which are more in line with recommended inputs). Several more trials are still being finalised, and we will keep you updated as we confirm their designs. It’s set to be a busy summer!

 

Whilst it might seem straightforward to many of you that vegetable growers should be applying the recommended rates, and creating a fertiliser plan that achieves optimum crop yield and minimises nutrient loss risk – there is often a huge amount of risk associated with these systems.

Many of the growers we work with cite crop quality, unpredictable weather events, and processing/retailer contracts as major constraints to adopting sustainable practices around minimising nutrient loss. Not to mention until February of this year, the most recent soil nutrition guidelines for vegetables in New Zealand were published in the 1980s.

A lot has changed since then, and environmental compliance is now a top priority for our growers to remain farming in their catchments. That is why LandWISE through FPVP is proud to support growers test and accurately measure the impacts of alternative management practices on a small scale through on-farm trials. We are passionate about helping growers achieve economic and environmental sustainability in their businesses.

If you are keen to learn more about any of these trials please contact Luke Posthuma (Precision Agronomist).

Digging Holes: An Intro to Soil Assessment at Leaderbrand

LandWISE visited Leaderbrand Gisborne earlier this week, where Nick Pollock, one of the Farm Production Managers there had invited us to hold a VSA, Fertiliser Equipment Calibration, and Quick N-Test Field Day. Nick ensured his tractor operators and crop managers were up to speed with good practice by encouraging them to take part in the day’s activities and share their experiences making day-to-day on-farm decisions regarding cultivation and fertiliser application.

Starting off the day with a fertiliser calibration, we were pleased to see the strong understanding of how to run a calibration test by their staff, and the use of practical charts to help drivers choose the right speed and revs for the field they’re working in and fertiliser product they’re applying.

Salad crops are a significant part of Leaderbrand’s production, and to accommodate this unique growing method, where planting densities are high, and crop maturity is reached in as little as 60 days, they have adopted new fertiliser application technologies which minimise waste. Calibration of these systems is especially critical to ensure uniformity of crop establishment during the short growing period and maximise the crop’s nutrient use efficiency. Using our calibration tool FertPlace, we were able to identify the application uniformity across the bed and calculate the application rate at a standard speed.

Visual Soil Assessment (VSA) – the process of assessing soil quality by eye and feel was developed by the soil scientist Graham Shepherd and has been around for a while (the first edition of the Visual Soil Assessment Field Guide was published in 2009).

Demonstrating this process in a nearby paddock, where Leaderbrand has been following controlled traffic systems for the past 5 years, showed some surprising results. The soil structure of the cultivated bed had significantly better porosity, stability of aggregates, and drainage characteristics when compared with the compacted “road” soil in the wheel tracks. The side-by-side comparison of the soil from the cultivated beds and a long term pasture soil from under a fence line in the same paddock showed that even a heavy Makauri Clay Loam soil can score well on the VSA when treated with care as Leaderbrand have committed to by adopting Controlled Traffic Farming.

Following this first look at soil characteristics under cropping, we visited a recently disestablished vineyard that is being leased by Leaderbrand for cropping in-between developments. The short break in production had allowed them to dig an impressive viewing hole that demonstrated the variability in soil structure, texture, and organic matter at different depths in the profile. As seen in the figure below, the Waipaoa Silt Loam profile has a buried topsoil (Matawhero Silt Loam) at 40cm depth, remaining from before the 1948 flood of the Waipaoa River.

To finish off the field day, a demonstration of soil sampling and using Quick-Nitrate Test Strips was completed for a Leaderbrand lettuce crop.

As part of FPVP, LandWISE is helping growers to adopt this tool as an in-field method to determine the soil supply of N during the growing season. More information about this test process and the proof of concept research, led by Plant and Food Scientist Matt Norris can be found here.

For those already using Nitrate Test Strips, the Quick Test Nitrate Mass Balance Tool which converts the Nitrate Test Strip results from ppm into a kg/ha Nitrate-N value can be found on the FAR website.

Our acknowledgement and thanks go to Leaderbrand Gisborne for supplying us with equipment to test, and setting aside their time to take part. We also gratefully acknowledge MPI’s Sustainable Farming Fund, and the co-funders of the Future Proofing Vegetable Production project for making field days such as this one possible.