Hemp Field Trials 

Raise the Roof

Hemp has been baled, reports have been written, video documentary completed – the year of growing, harvesting and processing Hemp as part of the Raise the Roof Hemp Field Trials project is coming to a rest – What a ride it has been! We’ve explored most of the pitfalls along the way, which has been interesting and challenging. Fundamentally we have learnt a great deal about Hemp – Critically we can now share that learning with others through the Field Trials Report and a short film produced by Chasing Cow Productions: 

A grant from the Dorset AONB Farming In Protected Landscapes Fund (FiPL), together with important match funding from Friends Provident Foundation, helped Wessex Community Assets Ltd (WCA) work with a group of West Dorset Farmers to explore the logistics of Hemp as a break crop and undertake field trials in growing, harvesting and processing Hemp. 

In total 10 Ha of Hemp was grown in the summer of 2022. Despite drought conditions, a healthy volume of Hemp was produced, about 3t/Ha. Key learning points from the Field trial include: 

  • Hemp germinates well and quickly provides cover that suppresses weed growth.
  • Hemp doesn’t appear to need any pesticide treatment.
  • Hemp grew well, despite the drought conditions in 2022. Nutrient application might have increased growth but results at Graston Farm suggest yield can be good without extra nutrient application.
  • Hemp provides dense cover, attractive as resting space for mammals, Deer and Brown Hare. The oily seed attracts red data book species Yellowhammers and Linnets.
  • A standard Forage Harvesters struggled with the thin fibrous stalks produced under drought conditions. A single bar cutter worked much more effectively. A Forage Harvesters were used to collect the cut Hemp and process ready for ensiling. Though contractors noted some ‘wrapping’ issues that would worry them for bigger harvesting jobs.
  • Cutting the Hemp long and leaving to ret worked well but there were issues with baling the Hemp that need to be addressed. Round baling, though problematic in the field trials, would appear the best option for collecting and storing cut Hemp.
  • More research is needed to understand what adaptions local baling equipment needs to be more successful with Hemp in the future. Not raking the cut Hemp into large windrows, instead leaving the Hemp thinly spread in the field and perhaps adapting the baler to avoid wrapping in the tight corners.
  • No issues were reported with the ensiled hemp.
  • In many respect it has been the small scale, old style machines that have proved most useful in harvesting and processing Hemp rather than the hi-tech industrial machines more commonly used by local contractors. 

WCA and an extended group of local farmers are keen to undertake further field testing of Hemp in 2023. Field testing would be extended to include organic farmers and different varieties of Hemp to better understand markets for seed as well as fibre and Hurd. Greater emphasis will be needed to resolve issues around baling long cut Hemp as well as more work on processing options and routes to market. 

‘Raise the Roof’ Hemp Field Trials 2022 Phase 2 Project Report
‘Raise the Roof’ WCA Hemp Field Trials Documentary Video