Soil Health Focus at Brassica Demonstration Day – The Vegetable Farmer – Will Sharpe, Oliver Wood, Carl Sharp, Peter Waldock

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IMG_0731With a focus on good soil health, herbicides, insecticides, biostimulants, fungicides, and nutrition, Hutchinsons’ second brassica demonstration day was held Old Leake, Boston, on July 11 in conjunction with the Allium & Brassica Centre.

The aim of the plots is to refine understanding of soil health, including exploring novel approaches for vegetable farming, such as strip-till and cover crops, explained Hutchinsons area business manager Will Sharpe.

“We plan to provide vegetable growers with a leading source of information on brassicas,” he said, pointing out that the trials field was very typical of the area, with similar soils being found around the horse-shoe area of south Lincolnshire and north Norfolk. “By setting up demonstration plots, people can see what works in these fields, and then make decisions on whether they might work at home for them.”

This year the demonstration plots were replicated, which proved to have been a very good decision as the site received 200mm of rain in just seven days in June, causing flooding in a number of areas.

Farmer and agronomist Richard (Rich) Daubney, whose family own the field, drew attention to the differences in how cover crops and strip tilling had improved how the soil had handled in the extreme weather. “The Brussels sprouts grown using a strip till regime look much better than those which were under a more usual strategy of ploughing and power harrowing,” he said.

This was further demonstrated at two soil pits on the site, situated less than 20m apart. Prior to becoming a trials site, the field had been under intensive cultivation growing potatoes, maize and vegetable in rotation. Pit 1 clearly showed compacted soils, whereas Pit 2, which had had a cover crop mix on it last year, had vertical fissures which would allow roots to develop downwards.

“Winter was dry and the soil structure looked very good, with no compaction. Then, in June, we had a huge amount of rainfall,” explained Rich, pointing out that many fields used for growing vegetables have deep compaction beyond where machines are able to reach, so growing a deep rooting plant, can help combat soil problems.

Oliver Wood with TerraMapAlso featured on the site was the TerraMap mapping service and precision farm management platform launched by Hutchinsons at Cereals this year.

“Today’s precision farming requirements demand greater accuracy so they can understand soil structure, and take decisions on crop choice, planting dates, irrigation scheduling, nutrient strategies and where to put drainage, said Hutchinsons precision technology manager, Oliver Wood.

“What is really exciting is that you can get a real time picture of the availability of nutrients, rather than a total account of what is just in the crop.”

He explained that TerraMap uses gamma-ray detection technology that delivers resolutions of over 800 points/ha, providing high definition mapping of all common nutrient properties, pH, soil texture, organic matter and CEC as well as elevation and plant available water.

“We have been looking for a new method of mapping soils that provides more accurate and repeatable results, and can also leverage the multi-layer analysis within Omnia,” said Oliver.

The results from TerraMap are used to create maps within the Hutchinsons Omnia system which can then be overlaid with additional field information to create accurate, consistent and detailed variable rate plans.

“The infield process of collecting the data is carried out in two simple steps; scanning by driving a light-weight all-terrain vehicle fitted with the sensor over a field, which indicates the reference points where soil samples to be taken.”

The basic level of information then shows soil properties and texture, but if the premium service is used, micronutrients, organic matter and cationic exchange capacity can also be monitored, he added. “There are 21 layers of nutrient or soil properties from 800 data points per hectare which are not affected by compaction, cover or moisture. Each scan is then used to create the individual map layers.

He went on to explain that TerraMap’s scanning technology is based on a scaled-down version of airborne sensors that originates in mineral prospecting, and has been used in other countries successfully. “It measures naturally emitted isotopes, like Caesium and Potassium, that are very stable due to their long half-lives. It is an entirely passive sensor.”

Prior to the launch, some 700ha of land were scanned to validate the data. “We took satellite imagery of fields that showed up areas of soil differences quite clearly and when we overlaid this with the texture maps created by TerraMap they were identical. This has been confirmed by in-field ground truthing across a number of sites. We have also tested the results between seasons and over different cultivations, and they have remained consistent.”

Rich said: “By building long-term layers of information this system helps identify some of the key things you may have been missing which have been impacting on crop quality and yield. “Over the last few years we have seen more and more extreme weather events, we need to ensure we give the crops the best chance to be resilient by providing the best possible conditions for them.”


Assessing pest controls in brassicas

Carl SharpThere is also a focus on new near-market chemistry, assessing rates and potential partners, in addition to seeking other mixes for already approved products, explained trials agronomist Carl Sharp from the Alliums and Brassica centre.

Since the loss of Cruiser (Thiamethoxam), there is nothing in the brassica toolbox for aphid control, partly because Verimark does not give consistent aphid control, he insisted. This means that crops may be susceptible to virus such as TuYV and TuMV.

 “To try and retrieve some efficacy against aphids, we have been assessing products applied with the precision applicator Phyto-drip. “Our aim has been to give growers different options for insect control by comparing foliar sprays with greenhouse applied controls.”

“We have one product in the pipeline which has performed very well and two other products which are available elsewhere put in to assess them in association with Verimark and Tracer for cabbage root fly protection.”

The trials site is also using an insect trapping device and two spore traps, one of which is sampled daily for white blister and ringspot.

Carl said: “Ringspot is the most prevalent fungal pathogen in this area of Lincolnshire, and the one you see first. If you treat for ringspot you are also treating for Alternaria.” The other spore trap is monitored weekly for light leaf spot. “This disease used to be located in Scotland, it then moved down to Lancashire and is now in Lincolnshire.

“Using a trap helps agronomists and growers because they can choose their product according to what they have found on-site.” 

There is also a weather station which helps informed decision making, he added.

Peter Waldock


Herbicide trials

Herbicide trials looking at crop safety also had different results from last year, with no crop safety issues this year, reported Peter Waldock, Hutchinsons technical support for vegetables.

“This year is very different from 2018, and weed pressure so far this year has been remarkably low – even the control plots have been very clean,” he said.

A cauliflower crop (variety Liria) was planted on 16 May and was treated with Verimark. Treatments 2/14 applied 20 May, treatments 15-16 applied 18 June. 


“Many of the new fungicides coming on the market are predominantly protectant rather than having a kick-back effect, so applications have to be better targeted to optimise efficacy,” said Peter.

The company’s brassica fungicide trials are due to start in the second half of July, examining each with a biostimulant to assess any differences.

“Our trials explore maximising efficacy in kale and Brussels sprouts, and the knowledge gained can then be related to all brassica crops.”


Nutrition trials

Moving on to talk about yield assessments, bacillus and bio-stimulants, in Brussels sprouts (variety Dagan) planted 16 May, Carl said: “All the products gave promising results.”

He drew attention to the efficacy of plant-based biostimulant Bridgeway, where a button-weight increase of 17 per cent had been found.

“This is partly because it improves the efficiency of plant metabolism and so in addition to yield increases and plant quality, the crop is also better able to tolerate the effects of stress.

“It is based on amino acids, so there is also a small amount of nitrogen also applied. The product is already being used successfully in the field, and is proving cost effective.”

They also found that Bacillus-based RhizoVital also performed well, increasing nutrient availability to plants by converting soil nutrients into more easily accessible forms for uptake into the plant.

“Trials have shown it worked well for early growth of seedlings and young plants, and improved uniformity. In addition, the Bacillus is compatible with synthetic fungicides.

Other products performing well included bioflavonoid mixture Cultigrow, and foliar nutrient complex Advance 66.

“One of the further benefits of good nutrition programmes is that they enhances plant health, creating the right environment for the plant to maximise its own defences.”

Peter added: “Biostimulant applications completed in the greenhouse are more cost-effective; this is partly because when you apply products early in the production cycle a lot of that product will end up a long way outside the early root zone and thus is not accessible to the crop.”