Field scale veg is often thought of as a cropping pattern confined mainly to the eastern side of Ireland yet, over in Co. Cork, there is a large acreage of onions grown by Castlecor Potatoes of Mallow.

The company grows two crops of onions: a winter and an autumn crop, with the latter now being harvested for the end of year trade, all of which will go to Lidl for retail sale.

Learning to grow onions alongside its main potato crop was something of a challenge for Castlecor Potatoes, as growing conditions are somewhat different to that of the UK, from where the company originally sought advice.

The main difference is that the west of Ireland has better growing conditions, and the first ever crop yielded well ahead of what was expected.

That lesson learnt, the company - along with the agronomist concerned - have since developed a system for producing onions suitable for the Irish market.

Part of the success Castlecor Potatoes has enjoyed is down to the company's ability to adapt machinery to suit the needs of an uncommon crop here in Ireland.

The home of onion-growing technology is The Netherlands, and it is there that Castlecor Potatoes has looked for machinery as well as a supply of seed onions.

The planter is a manned unit, with the seat required not for someone to plant the bulbs but for an operator to keep an eye on the machine's working.

However, Alan English - nephew of Ned English who formed the company - decided instead to install cameras on the planter and a screen in the cab, alleviating the need for a person on the machine.

Once the time for harvesting has arrived, a specialist topper is required to remove the leaves on the crop.

This machine has large flat blades that create an up-draught, lifting the leaves off the ground to be sliced off at the level of the onion neck.

Once the leaves are removed, the neck of the onion is left to seal - for onions will rot from the neck down and it is important that pathogens are not given the opportunity to establish themselves in this area.

A few days after the leaves are removed, the bulbs are then dislodged from the ridge by another specialist machine and left in rows for the harvester.

The Castlecor Potatoes approach of adapting whatever is available has extended to the harvesting machinery, with two machines ready to pick up the crop once it has been windrowed.

The machine in use when Agriland visited was a Grimme GT170, a machine built for harvesting potatoes in France and not sold in Ireland.

While visiting the Grimme factory in Germany, Alan noticed that this model series would be suitable for picking onions if the rear end was configured to suit their needs.

A second hand unit was then sourced from France and brought to work in Co. Cork, where Alan himself adapted the pick up for the job.

The advantage, he notes, of this machine is that the dust is kept well away from the tractor, reducing the need to blow out the filters on a regular basis while also making life a little more bearable for those in the cab.

However, what does detract from the comfort is the row crop wheels, which - despite the presence of cab and axle suspension - do jolt the operator around when turning at the headlands.

One great advantage of harvesting onions is that they are a lot more robust than potatoes and, so long as they are dried and cooled properly, have a long shelf life.

This is done back at Castlecor Potatoes main yard, where the onions are stored in boxes designed to channel air through the bulbs and in a shed adapted to supply cooling air to each layer of crates.

Onions make an excellent break crop and will usually be followed by wheat, which tends to provide an enhanced yield the following season.