ONE OF the biggest changes to the Swede growing industry in recent years has been an improved flexibility in lifting systems and the use of grown up harvesters.

The knock on effect for Stewarts of Tayside, one of the biggest soft fruit and vegetable packers in Scotland, is that their recently purchased Grimme GT trailed harvester has given a quality boost of more than 5% and better pack out.

Commercial director, Liam Stewart, who runs the business with his father, William, said improving pack out means a potential reduction in total acres needed for the same output.

“The harvester is such an important part of the growing process and each time we buy a new one we always try to make improvements on the previous one. The build quality of the GT harvester has resulted in a machine that is gentle to the crop,” he pointed out.

The company grows Swedes all over east Scotland and supplies supermarkets for 52 weeks of the year, with a harvest of 10 months. Fruit harvest starts when the Swede harvest slows down, which ensures good utilisation of labour, facilities and machinery, according to Liam. During the peak harvest period from December to February, it is all hands to the pump.

“Harvesting Swedes can be quite erratic because we lift to order,” added Liam. “Once all the soil and tops have been removed we are looking at around 55% pack out.”

The majority of the harvesting operation is achieved with two Grimme GT machines, but in peak periods two older machines (GZ, Variant) are drafted in. Running one self-propelled machine has been considered in the past, but he said that the risks of relying on one machine were just too great.

“And, with such a small second hand market for a specialist machine, it would only command a poor residual value. At least with a Grimme trailed machine, it can easily be converted back into a potato harvester and that leads to a better residual value."

The harvester has been designed and built to Stewarts' specification, based on using Dolman rollers in the wet and a web cleaning system in the dry. The latest GT has an electronic switch over facility for the cleaning system as well as a new design of the cart elevator web, which is lighter and has softer, more flexible flights.

“With our old kit it used to take a full day to change from one cleaning system to another, but now with a flick of a switch from inside the cab it only takes 20 seconds,” said Liam.

“Lifting swedes on abrasive and stony soils means we will normally look to replace two or three cart elevator webs in a season across the harvesters. The fact that the new elevator webs are lighter should mean it is less expensive to replace and maintain.”

Tractor mounted front toppers mulch the green top before lifting shares take the crop onto the main web and then the second web and contra rotating rollers. There is no picking off facility.