Peas increase wheat yields and lengthen OSR rotation

After a 40-year break, Norfolk farmer Chris Eglington reintroduced peas to the farm in a bid to widen his oilseed rape rotation and promote yields of following winter wheats.

The leguminous break crop successfully achieved what Mr Eglington hoped it would, acting as an excellent soil conditioner to increase yields of subsequent milling winter wheat.

Peas also improved both establishment and yield of oilseed rape by extending the rotation to one in eight, which considerably reduced cabbage stem flea beetle pressure.

See also: Essex wheat grower earns extra premium by hitting 14% protein

Growing demand 

With demand for pulses growing and new markets opening up, there are considerable benefits and opportunities available to growers.

Given the record high fertiliser price, growing legumes may become particularly appealing as they don’t need any nitrogen fertiliser.

With this in mind, Mr Eglington planted 34ha of the large blue variety Mankato this season, which was drilled into good conditions, with moisture at depth and dust flying on the top.

However, given the volatility of pulse markets, he questions how much longer he will continue to grow the crop at the 400ha farm (285ha of which is cropped), trading as SS Eglington and Son, based at Letton.

“I find myself asking whether I should continue to grow peas. We have to appreciate the price of fertiliser, which is extortionately high, but with oilseed rape now at £800/t, markets will have to adapt for peas to really pay,” he says.

Peas can be difficult to harvest, so a flexi header can help © Chris Eglington

Lack of investment

n fact, when he first grew peas 40 years ago, average yields were 5t/ha. He then dropped the crop from the rotation as he introduced more grass leys for livestock across the farm.

Fast forward to today and his pea yields are no more than they were four decades ago, despite new breeds and developments within the pulse sector.

This is mainly due to the lack of investment and research into the UK pulses and veg legumes sector, explains Roger Vickers , chief executive of the Processors and Growers Research Organisation.

Pulses and legumes are niche crops, with less than 250,000ha grown each year. This niche crop status has, therefore, minimised commercial investment and research funding over the years, meaning crop improvements have been limited.

“On a global scale, an estimated US$175m [£134m] is invested annually in pulses and legumes, compared with billions for crops in the ‘big seven’,” says Mr Vickers.

He point out that supply and demand is often restricted as poor crop data and variable crop quality hampers market developments. “We usually don’t know what area of pulses there is planted until after harvest, when Defra releases its results,” he says.

Despite this uncertainty, markets are evolving and when it comes to creating a sustainable rotation that increases crop productivity and encourages biodiversity, growing pulses can bring huge opportunities and benefits.

Sheep graze stubble turnips, before planting to peas in the spring © Chris Eglington

Establishing peas

When it comes to high-yielding crops, cultivations and establishment are absolutely critical, says Mr Eglington, as pulses are particularly sensitive to compaction.

Last year, when establishing the crop he made two passes before drilling. The first with a Vaderstad Carrier to break up the surface and help the soil dry out after winter, while the second was with a Vaderstad TopDown. This removed a layer of compaction identified at 15cm deep as a result of sheep grazing the prior crop of stubble turnips.

However, he admits that two cultivations are not always necessary and with the cost of fuel rocketing he used just the one TopDown pass, before drilling with a Vaderstad Rapid at a depth of 13cm.

Mr Eglington opts for a high seed rate of 250kg/ha, and uses variable-rate drilling as soil types range from very heavy to relatively light land. This results in variable rate range of 208-267 seeds/sq m.

To further reduce compaction risks and maximise root systems development he uses a 8m controlled traffic farming system with variable-rate tyre pressure set at 0.62bar (9psi) when working on pea ground.

Nutrition also plays a major part. Biosolids are applied after winter barley and in front of stubble turnips, which are in turn grazed by sheep. This eliminates phosphate requirements, but 100kg of polysulphate for sulphur and variable-rate potash are still applied.

With fuel costs rocketing just the one TopDown pass was used © Chris Eglington

When it comes to disease control, a total of two fungicides are applied. One at the early- to mid-flowering stage and the next at post-flowering.

Mr Eglington is a strong believer in on-farm trials, so a number of rates were investigated on different fields. On average this was 0.5 litres/ha Signum (boscalid + pyraclostrobin) followed by 0.375 litres/ha Amistar (azoxystrobin).

He intends to use a similar programme this year, but also trial a three-tired fungicide spray programme and monitor any yield differences. Insecticides are only used if absolutely necessary. However, he notes that one of the main challenges associated with growing peas is harvest.

“Crop losses can be an issue. We definitely grow more in the field than what we harvest, but we use a Claas Flexi header with specific knives for peas to help scoop the crop up,” he says.