Category Archives: Crop Nutrition

Phosphate Starter Fertiliser for Onions?

Some growers have observed that adding phosphate fertiliser at planting time seems to improve the growth of onions, especially at early stages.

To test this, we’ve set up a small trial with our Ballance AgriNutrients partners. In each of 5 small plots, we placed the equivalent of 250 kg/ha of triple superphosphate 50 mm below and beside the onion seed.20150814_170007_P-Trial_640

We’ll track development of the plants in the treated plots and in corresponding neighbouring plots to see if there is a significant difference.

Why five plots?

Having replicated plots means we can better understand if any differences are “real” or “due to chance”.  We know there is always variation in any paddock in any crop, so how can we tell if our treatment (added P) caused any difference we see?

In crude terms: If the difference between our “Plus-P” plots and our “No-P” plots is greater than the difference between the different “Plus-P” plots, we can assume the difference is real.

Generally four replicated plots would be OK for a first look at something like this. It lets us run an ANOVA test to check statistical differences. We put five plots in, partly to cover the chance of one being damaged by field operations including turning our irrigator.

Check out the LandWISE/FAR “On-Farm Trial Guide” series for explanations and templates if you want to do a trial that you can really learn from. It includes a downloadable spreadsheet that will do your ANOVA stats and interpret the result for you.

Thanks Ballance  Ballance web150

Monitoring Variability in Onions

Our first MicroFarm onion crop is extremely variable. The view below was taken from on the linear move irrigator, a useful vantage point

Variability is obvious when viewed from the irrigator
Variability is obvious when viewed from the irrigator

We want to measure variability so we can better assess it. If we can measure objectively we can make better decisions. We are interested in spatial variability and temporal variability.

The image above shows spatial variability: some parts of the paddock are better than others. We want to understand why some plants have done quite well, while others have done very poorly. If we can identify patterns, it can help us identify causes.

There are two patterns showing up in the image. There seems to be a large area where growth is poor. Perhaps that is a lower, wetter area? We can also see that every third bed is stronger than those on either side. That pattern is quite strong across the whole paddock and matches planting pattern from our three bed planter.

We wanted to map our crop so we could look for more patterns. We took a GPS connected sensor that measures the amount of ground cover and went up and down the beds.

Ground cover map of MicroFarm onion crop from data collected in early December

In the image above, the sensor data is displayed as a colour scheme. Green is highest ground cover (the biggest plants and most continuous planting). Red is lowest ground cover (small plants or larger gaps between plants or both). We used a cheaper GPS without correction so our bed readings have strayed off line. But even still, we can see the same pattern as in the photo above.

Will this pattern reappear in future years? Temporal variability seeks to understand how crop performance changes from year to year. If we can identify “always high”, “always low” and “sometimes high/sometimes low” areas we can develop management strategies to suit. Sensor based mapping is one of the best ways to identify such zones.

2014 Peas – crop summary

Tasman Harvester Contractors dealing with wide pea maturity range - crop harvested early at average TR=91
Tasman Harvester Contractors dealing with wide pea maturity range – crop harvested early at average TR=91

With four of our paddocks in vining peas this spring, we keenly awaited the harvest. It came late, but still early . . .

High levels of damage in the more tender areas reduced yield
High levels of damage in the more tender areas reduced yield. Both lots from same sample and at same scale – peas on left mature, on right immature and damaged during harvest

All four paddocks were planted on 29 August by Patrick Nicolle using a 3m Great Plains drill. Significant damage done by pigeons at all stages from planting through germination and early growth. Tim Geuze implemented a bird management programme.

We plan to use Cosio covers on plots in paddocks in future, in part to assess the degree of bird damage we suffer.

We know from weather records that this spring was cold. FAR‘s Maize Action news shows that Hastings had only half the average Growing Degree Days from 15 September to mid-December. Cold weather means crops mature slowly, and we certainly saw a long period of flowering in the pea crops.

We did receive higher than average radiation – the factor that most drive biomass growth. And we did see good canopy development.

The paddocks received about 75mm of irrigation as four lots from the linear irrigator. HydroServices recommendations were based on neutron probe monitoring in P3 and P4. The data show that the paddocks used the same total amount of water but from different parts of the soil profile.

With drawn out flowering and cold temperatures, there was a wide spread of pod fill across and within the Paddocks. P3 and P4 continued flowering up until harvest. Some base pods were over optimum maturity (TR ~ 130) while others were only just beginning to fill.

An extended flowering period gave wide range in pea maturity - difficult for harvesters
An extended flowering period gave wide range in pea maturity – difficult for harvesters

The average results across all four paddocks were:

  • TR 91
  • Net Weight 11.040 t
  • Deductions (%) 4.6 %
  • Paid Weight 10.532 t
  • Paid Weight 4.713 t/ha

Autumn Open Day

Website Open Day StripThe LandWISE MicroFarm held its second Open Day in April 2014. The two crops for discussion were sweet corn and green beans.

MicroFarm IrrigationWeb

Green beans are a relatively new crop here, and questions over best management remain. The MicroFarm Discussion Group selected a few options this season.  Some may require following up with more investigations.

Plant arrangement and population

Tasman Harvesters Director, Gary Cutts returned from a trip to Europe where he saw most green beans are planted on 15” or 381mm rows. Gary was very keen to try the narrower row spacing. He has noticed smaller canopy crops that do not fully fill the allocated row space are difficult to harvest well.

This season we have planted one MicroFarm paddock at 15” or 381mm spacing, increasing the in-row spacing to keep the population near the norm.  At half the usual spacing for crops such as process sweetcorn or maize, fitting tyres into the mix is a challenge.

McCain Foods Field Officer, Ben Watson was interested to know what plant population might be optimal. He set up four rates from 300,000 to 370,000 plants per hectare.


Ballance AgriNutrients’ Mark Redshaw has used double rate phosphorous in one half and no phosphorous in the other. Other nutrients are the same, at rates determined following soil testing at Hill Laboratories.

Herbicide strategy

Scott Marillier and Vaughan Redshaw at Fruitfed Supplies selected a standard herbicide programme for most of the area. Haydn of Greville Groundspraying applied 600mL/ha BASF Frontier and 500mL/ha Magister as a pre-emergent spray. This was followed by 3L/ha BASF Basagran (Bentazone) at two trifoliates.

In two half paddocks, they left out the pre-emergent, and applied 1.5 L/ha Basagran (bentazone) at cotyledon stage, then 3 L/ha at 2 trifoliates.


By the end of February the buried drip installed by ThinkWater had applied four 10mm irrigations. That was enough to keep just above stress point. In early March the crop justified 10mm applications every two days. We are seeing some bypass as the deeper soil shows increasing moisture. The outside rows planted are outside the area irrigated with drip. The differences are very evident.

HydroServices’ soil moisture monitoring showed the un-irrigated paddocks were stressed from early on. Funding constraints have prevented us getting the dream irrigation system so we started using our mini-gun, applying 35mm at the end of February.  While adequate on pasture, it is not ideal for crops.

Irrigation has continued with a second round in early March applying another 35mm. Windy conditions at the start of the month affected application patterns, and some days we did not bother irrigating at all. View the edges of the paddocks to see the difference!

The Netafim dripline extends under the first part of the sweetcorn in paddock 3. Again, the difference between irrigated and unirrigated is extremely obvious.

More information on the main LandWISE website

Many thanks to:

Centre for Land and Water, ThinkWater, Netafim, HydroServices, McCain Foods,
Ballance AgriNutrients, BASF Crop Protection, FruitFed Supplies, Agronica NZ,
Nicolle Contracting, Te Mata Contractors, Drumpeel Farms, Greville Ground Spraying,
True Earth Organics, Tasman Harvesting, Plant & Food Research and Peracto Research for support with this work.

Foundation MicroFarm Sponsors

Ballance web150  BASF web  CLAW-light-150

Green Beans Planted

MicroFarm Paddocks 1, 2, 5 and 6 have been planted in Green Beans, destined for McCain Foods in Hastings.


These paddocks were previously in vining peas, and issues with compaction and paddock humps were noted. See the post, Removing Compaction for more details.

A number of different options are being observed, including:

  • row spacing
  • plant population
  • varieties
  • fertiliser programme
  • herbicide strategy
  • drip irrigation dryland
  • and hopefully spray irrigation

Row spacing

At the instigation of Gary Cutts of Tasman Harvesting, responsible for harvesting the beans in Hawke’s Bay, Paddock 1 has been planted with a 15″  (381mm) row spacing. This compares to the standard 20″ (508mm) spacing in the other three paddocks. (Originally beans here were planted on 30″ (762mm)rows.)

Gary has noted that in lighter canopies planted on wider spaced rows, some beans get lost at the edges of the harvest swath. He believes we should try the closer spacing which is common in Europe.

Others in the MicroFarm discussion group has raised the potential increase in disease risk with a more closed canopy, so this will be monitored with interest.

Getting the beans planted at the narrow spacing was a challenge as the Monosem NG plus 4 planter being used would not close up enough. The units are capable, but the current toolbar arrangement with wheels in the way is not.

Instead, Patrick and the Nicolle Contracting staff used their John Deere 8-row MaxEmerge XP planter set on 30″ spacing, and simply moved the whole machine across 15″ to do intermendiate rows. This resulted in some planted rows being driven over – the group decided that was an acceptable limitation for a first look.

Preparing the JD MaxEmerge for 15″ row planting

Rain after planting may have aided emergence even in these rows although it may be delayed and less successful.

Tough bean seedlings emerging through wheel track

Plant Population

Ben Watson of McCain Foods is leading a plant population comparison in Paddock 6. Here four different plant desities are being tried, all on the standard 30″ (762mm) row spacing planted with the Monosem planter.

Population/ha                           In-row spacing

  1. 377,358 (standard)            5.3 cm
  2. 363,636                               5.5 cm
  3. 333,333                               6.0 cm
  4. 307,692                               6.5 cm
Bean planting P6 Airey 4 web
Planting the population trial with Nicolle Contracting Monosem

Fertiliser Programme

Ballance AgriNutrients’ Mark Redshaw developed a fertiliser programme based on soil test results and crop requirements. Paddocks 1, 2 and 6 each received 250 kg/ha Mila complex at planting.

As an alternative, Paddock 5 received no nitrogen at planting. The southern half received a double rate of phosphorous, and the northern half received no phosphorous.

Herbicide Programmes

The northern half of Paddock 2 and southern half of Paddock 5 (both nearest the centre access track) are receiving an alternative herbicide programme. The rest is being treated with a relatively standard approach.

Standard Programme                             Alternative Programme

Pre Emerge                                              
600 mL/ha Frontier                                  No product applied
500 mL/ha Magister

Cotyledon Stage
No product applied                                 1.5 L/ha Bentazone

2 Trifoliates
3 L/ha Bentazone                                    3 L/ha Bentazone

BASF supplied Bentazone and Frontier. FruitFed Supplies sourced Magister for us.

All herbicides are being applied by Haydn Greville Groundspraying

Soil Moisture Monitoring

HydroServices installed neutron probe access tubes in Paddock 2 (dripline) and Paddock 5 on 14 February.

20140214_neutronprobeinstal 20140214_neutronprobe

Results from soil moisture monitoring are posted on the Irrigation Monitoring page.

Sweetcorn Planted

MicroFarm paddocks 3 and 4 were planted in sweetcorn on 18 December 2014. This is destined for McCain Foods in Hastings.

Following harvest of vining peas, the paddock was sprayed off with glyphosate by Hayden Greville Groundspraying. Key weeds were Indian Doab (Cynodon dactylon) but others including Bindweed (Convolvulus arvensis?) and the usual Heretaunga Plains crop weeds were noted.

The paddocks were strip-tilled by Drumpeel Farms on 13 December using the 12 row Orthman strip-tiller.


A video of Hugh Ritchie with the machine was made by James Powrie of Eco-Eye with funding from and the Queensland Department of Agriculture, Fisheries and Forestry.

The sweetcorn was planted on 18 December by Nicolle Contracting using their John Deere 8-row MaxEmerge XP planter.

WP_20140131_016 web

On 9 January 2014, evidence of Cutworm and Argentine Stem borer justified Haydn Greville Groundspraying applying Agronica Alpha Scud (Alpha Cypermethrin) at 200mL/ha in 300-600L of water.

Fertiliser application plans were  Mark Redshaw. At planting Paddock 3 received 150 kg/ha DAP/PhasedN supplied by Ballance AgriNutrients. It was sidedressed between rain showers with 200 kg/ha of Sustain on 1 February 2014.

The Paddock 4 sweetcorn received 250 kg/ha Cropzeal 20N at planting. This was supplemented on 1 February 2014 with a side dressing between rain showers of 200kg/ha urea supplied by Ballance AgriNutrients.

Soil moisture monitoring by HydroServices has shown the crop reaching deficit levels. With no irrigation option for these blocks, we were to some extent saved by regular rainfall but are actively seeking a suitable irrigation option. Monitoring data are posted in Irrigation Monitoring.

Spot spraying with Agronica Leopard  to control remaining spots of Indian Doab was started on 4 February

Estimated harvest date is early April, before the frost.

Starter Nitrogen for Vining Peas


One question raised in the MicroFarm Discussion Group was whether a starter fertiliser might enhance vining pea yields.

MicroFarm soil testing showed bckground fertility was good. So it was questionable whether to apply anything. Numerous Plant & Food Research and Foundation for Arable Research trials have demonstrated no economic response of seed peas to applied fertiliser. Would vining peas be any different?


Mark Redshaw, our Ballance AgriNutrients Advisor, put a simple comparison together in Paddocks 3 and 4, both planted with the same Ashton variety on the same day.

Background soil fertility (0-15 cm) was measured before any fertiliser was applied. Available N was 121 in Paddock 3 and 82 kg N/ha in Paddock 4. Other key fertility indicators (pH, Olsen P, MAF K) were within optimum ranges suggested for peas in both paddocks. The only limiting factor was Sulphur. Sulphate levels ranged from 1-3mg/kg.


At planting:

  • Paddock 3 received 100 kg/ha of PhasedN (25.3%N, 28.5%S and 5.7%Ca)
  • Paddock 4 received 100 kg/ha of Sulphur Gain Pure (95%S)

Soil conditions were not ideal with moisture levels quite high, and compromises being made around fertiliser rates due to size of paddocks.

The fertiliser was applied with the planter to avoid an extra pass- but separation of product and seed was compromised due to soil conditions. High slug numbers were noted.


With the exception of fertiliser practice both paddocks were managed identically during the season. Neither paddock was irrigated.


Paul Johnstone, a Plant & Food Research member of the Discussion Group, and colleagues observed the comparison, took measurements and analysed the data collected.

At maturity they harvested plants from three sample areas (each 0.75 m2) in each paddock. For each sample they:

  • Determined the plant population
  • Calculated total plant biomass and fresh yields
  • Calculated the key components of yield (number of pods per plant, number of peas per pod, and mean mass of individual peas)
  • Measured quality using TR score.



Visually, Paddock 4 appeared to have a weaker canopy throughout the season. Soil investigation also indicated the paddock had poorer soil structure related to historical compaction.

Plant population

Paddock 4 had more plants per m2 than Paddock 3 but there was little evidence to suggest this was related to the starter fertiliser. In both paddocks, plant populations were considerably lower than the planting target of 110 plants per m2.

Crop roots were not inspected for nitrogen fixation activity.

Yield and yield components

Overall fresh yields varied greatly, ranging from 7.8 to 13.8 t/ha across the individual samples. On average there were between 5-6 pods per plant, with each pod containing 6 peas averaging around 0.4 g per pea.

Starter fertiliser practice did not affect total plant biomass, fresh pea yield or the components of yield (pod number, pea number and mean pea mass) even when variable plant population was considered.


TR scores were 120 in Paddock 3 and 126 in Paddock 4. These are higher than optimal for processing (usual target is 110-115) indicating that the crop was harvested a day or two late.

There was no effect of the different starter fertilisers on TR scores.

Bottom line

At this site there was no evidence of a yield or quality response to increased N supply at planting.

This was despite a visually weaker canopy where no N fertiliser was applied. The canopy weakness may have been related to soil compaction in the paddock rather than N deficiency.

Pre-trial soil available N measurements showed fertility was moderate in both paddocks. This might have masked any crop responses to the applied fertiliser treatment.

So this comparison supports research that, at least on moderately fertile paddocks, there is no benefit from applying starter fertiliser to vining peas.

Thanks to Ballance AgriNutrients, Hill Laboratories, Plant & Food Research, Nicolle Contracting and the Centre for Land and Water for their support with this MicroFarm study.

ballance_logo_100  HillLabs100  PlantandFoodweb100  nicolle_contracting_100  CLAW-light-100


Open Day

The first MicroFarm Open Day was held on Thursday 5th December. The event received significant media coverage, including a two page spread in Rural News.

We are grateful for the excellent presentations made by our speakers, and for the quality of discussion that followed. Attendees travelled from South Canterbury, Manawatu and Gisborne to join local growers, contractors and their support industry colleagues.

Sarah Pethybridge’s presentation on Plant Growth Regulators helped understand this complex topic. The first demonstration results were being assessed, samples having been harvested the day before.


Short “theory” presentations in the Green Shed

  1. Why a MicroFarm; what we expect to learn – Dan Bloomer, LandWISE (and others)
  2. Soil nutrient picture; what we found, what we’ve done – Mark Redshaw, Ballance AgriNutrients
  3. Inoculants for legumes; our first trial and hopes – Weston Hazelwood, BASF Crop Protection
  4. Plant Growth Regulators; compressing pea flowering – Sarah Pethybridge, Plant & Food Research
  5. What the MicroFarm still needs – Dan Bloomer, LandWISE

Outside practical demos and discussions

  1. Buried drip for vegetables – Anthony Waites, ThinkWater
  2. Soil moisture monitoring; water use messages – Melanie Smith, HydroServices
  3. Soil compaction; penetrometers, VSA and a plan – James Powrie, Hawke’s Bay Regional Council
  4. Herbicide selection – Vaughan Redshaw, Fruitfed Supplies
  5. Plant Growth Regulator treatments; a first scoping study – Tim Robinson, Peracto

Download a printable pdf Open Day Programme here

The MicroFarm is a genuine community activity, as shown by the sponsors and supporters listed below. We are unsure of all the outcomes, but we know there will be much learning along the way.


September 2013: Fertiliser recommendation for early peas

Fertiliser recommendations for peas

Mark Redshaw, Ballance Agri-Nutrients

Based on the soil tests taken in June from sites 1 – 6, the background fertility at the MicroFarm is generally high with the only limiting factor being Sulphur. Sulphate levels ranged from 1-3mg/kg.

With numerous trials demonstrating no yield response to applied fertiliser it was questionable whether to apply anything. See, for example, Foundation for Arable Research Updates

Earlier MicroFarm Discussion Group members had raised the question of additional nitrogen, in particular in relation to vining green peas for processing rather than for dry seed.

With the early and late plantings occurring, and the questions being raised about starter nitrogen and the use of inoculants, the following was recommended:

  • Early Peas Block 3 100kg/Ha PhasedN- Nitrogen/Sulphur treatment (25N 29S)
  • Early Peas Block 4 100kg/Ha Sulphur Gain Pure- Sulphur Treatment (90S)
  • Late Peas Block 1 No fert
  • Late Peas Block 2 No fert -Inoculant- Nodulaid
  • Late Peas Block 5 No Fert -Inoculant- Nodulaid
  • Late Peas Block 6 No Fert

This will enable a few comparisons:

  • Nitrogen/Sulphur versus Sulphur treatment.
  • Innoculant treatment planted into previously grass versus previously broad beans.
  • No fertiliser comparisons planted into previously grass versus previously broad beans.

Soil conditions at planting were not ideal with moisture levels quite high, and compromises being made around fertiliser rates due to size of blocks.

Ability to apply fertiliser with planter was used to avoid an extra pass, but separation of product and seed was compromised due to soil conditions.