06 June 2025

Inter cropping challenges

A push for home-grown protein, an influx of livestock farmers having converted or converting to organic production and the availability of Protein Aid scheme has made inter crops – a combination of cereals and legumes – an attractive prospect for many organic tillage farms.

Despite the positives, challenges do exist when it comes to optimising the production of both the cereal crop and the pea or bean legume present.

As part of a Teagasc Organic Crop Walk on the farm of Rod and Julie Calder-Potts, Highbank Farm, Cuffesgrange, Kilkenny on May 29, Teagasc Organic Specialist, Martin Bourke reminded those in attendance of some key considerations when growing inter crops.

“There is potential for organic tillage farmers to produce inter crops for the organic animal feed market, but having a secure market is vital before establishing. These crops, both high in protein and energy, are desired by organic livestock producers as an alternative to organically certified concentrate feeds.”

Unlike many conventional cereal producers, where the end product is delivered to a merchant or grain handling facility, organic tillage farmers growing inter crops are often producers and marketers.

Given this, one farmer in attendance suggested that an organic merchant willing to buy such inter crops would be beneficial for producers. Where farmers don’t have the option to deliver to a merchant, Martin Bourke reminded them of the importance of having sufficient storage and handling infrastructure after harvest, an element that is very important as grain moisture levels can be higher in comparison to other cereal crops.

Martin Bourke, centre discussing inter cropping at the Teagasc Organic Crop Walk at Highbank Farm, Cuffesgrange, Kilkenny

Next up was a discussion on the seed ratio of cereals to legumes – much of which will depend on the end market for the crop, but generally ratios of 50% cereal to 50% legume are grown. Where barley is included in the mix with pea, Martin Bourke suggested pushing the ratio of the former up to 60% as modern barley varieties are not as proficient at scavenging for nutrients when compared to crops such as oats.

Also detailed at the event were the results of analysis of nine organically grown inter crops harvested last autumn. As evident in table 1 below, a big variation in the quality parameters was observed through the laboratory analysis, with Martin Bourke pointing to two specific reasons why such variation existed – pigeon grazing and difficulties harvesting.

Table 1: Inter-crop analysis from nine different farms

“Where peas are grown” Martin Bourke explained, “pigeon grazing can be a challenge during the early establishment phase. Often occurring in open, poorly established crops, pea content struggles to recover, the peas available at harvest are lower and the overall protein content of the inter crop is reduced.”

Additionally, where farmers are considering including peas within the inter cropping mix, Martin Bourke urged them to pay careful attention to its straw strength, favouring varieties such as Ingrid, which is proven for straw strength without compromising on yield.

“As pea pods are present on both sides of the stalk, where the pea fails to stand up two things occur that lead to losses at harvest. The pods at the underside of the lodged stalk have difficulty ripening due to the lack of light, whereas the pods on the upper side become overripe and shatter, leading to yield losses.

“Where peas are included, really focus on the straw strength. We really need the crop to stand up to realise the benefits at harvest,” Martin Bourke explained.

Another potential solution discussed was including both pea and beans at a 25%:25% ratio within the inter crop, allowing farmers to mitigate risk in either really dry or wet years as each crop has its own distinct preference. Where such an option is chosen, matching the ripening date of the pea, bean and cereal crop is critical.