Amid intensifying cost pressures, plasma technology can help salad and herb growers increase yield by as much as a quarter, company claims

Zayndu has achieved significant yield increases in seed trials

Zayndu has achieved significant yield increases in seed trials

With producers hit by energy price hikes, a seed treatment called Zayndu could help salad and herb growers to boost their yield by 10-27%, the company has claimed.

The Zayndu Aurora System uses low-energy plasma-technology to treat seeds in small batches prior to planting. The treatment delivers ‘activated air’ created by a cold plasma to improve seed health and improve overall plant yield. It takes minutes to complete and produces no waste, according to the company.

The system works by improving the consistency and rate of germination as well as the speed at which the seedlings grow – which, in turn, increases the yield and throughput for the grower.

In trials, the technology has achieved the following yield increases: 10% on chives and parsley, 15% on coriander, and 27% on dill.

Furthermore, the Aurora system claims to increase the germination of spinach from 80% to 95% and accelerate the process by approximately 1.5 days. Leafy greens have short growth cycles with germination times of 2-3 weeks and a total lead time of 4-8 until harvest, depending on crop. Therefore, shaving 1.5 days from each cycle can increase throughput.

Recent research by Promar International for the NFU showed that plantings in the controlled environment horticulture sector have been scaled back by up to 20% this year, with many growers reported to be walking away from contracts and considering withdrawing from the sector. Autumn and winter planting in heated glasshouses will be reduced due to energy costs.

Business consultancy firm Camrosh recently completed an analysis of the energy requirements of the controlled environment horticulture sector for Defra, in collaboration with the Institute for Manufacturing at the University of Cambridge.

The company’s director of research and operations, Bernhard Strauss, said: “The pressure on growers is only likely to accelerate, especially in the high-tech glasshouse sector as energy costs remain staggeringly high.

“Even more so in vertical farming where typical electricity inputs per year are ~300kWh/m2 for heating, ventilation and air conditioning (HVAC), dehumidification systems, pumps etc. plus ~700kWh/m2 for lighting, so with energy costs increasing by 156%, commercial viability is a real issue.

“Hence, a possible yield increase in the range of 15% without additional inputs would be of great interest to the vertical farming sector and for different types of glasshouse and polythene tunnel growing. Achieving consistent yield increases at this level by another method would need an increase in material inputs or labour.”

Leafy greens such as lettuce and herbs (including basil, cress, chive, parsley, dill and coriander) are still largely grown in different types of low-tech greenhouses and polythene tunnels, but Zayndu pointed out that they are particularly well suited to vertical production, which can allow for as many as 20 harvests per year.

Research by Intelligent Growth Solutions (IGS) found that shelf life is longer for vertical farmed produce, with lettuce lasting three weeks (compared to one week for open field crop). This means less waste and lower water use, with 250l/kg used for field lettuce crops compared to 1 l/kg in a vertical farm.

Strauss said: “Although energy input per unit crop is still much larger in vertical farming compared to growing under glass or polythene tunnels, where natural light and ambient temperature is used at no cost, creating opportunities to increase productivity will help make vertical farming more commercially viable, particularly in extremes of climate where other resources are scarce.”