Know Your Roots

A technique to accelerate the production of ornamental species by ‘air root pruning’ is now demonstrated in Northern Ireland. Initially investigated by CAFRE (College of Agriculture, Food and Rural Enterprise), Greenmount Campus and AFBI (Agriculture, Food and Bioscience Institute) Loughgall, to accelerate the growth of trees, the method is now adapted and demonstrated for ornamental species.

At an event on Accelerated Production Systems, Teresa Maguire, Horticulture Technologist at CAFRE, Greenmount Campus, highlighted the technique of ‘air root pruning’ to accelerate the production of ornamental species.

“We have demonstrated that two year old Abies, Cordyline, Ilex etc., are at least double the size of those produced using traditional methods. Using commercially available propagation modules which induce air root pruning from an early stage, various ornamental species could be propagated from seeds or cuttings. These young seedlings can be transplanted direct to large containers without going into intermediate size pots, thereby saving time and labour”.

Richard Stevenson from Jiffy Products, UK, highlighted that the air root pruning technique is used in Scandinavian countries for the production of forest species.

According to Richard,

“Good roots produce good plants. Root pruning from the germination stage encourages more lateral roots to be produced to make good vigorous plants. This technique is applicable not only to forest species but also to ornamental and vegetable species”.

John Billington from Northern Liners who supplies young plants to nursery stock growers and multiples in the UK, confirmed our findings at Greenmount. According to John,

“Using preformed modules which induces root pruning for a wide range of species, enabled quality plants to be produced, saving time and costs. With no root disturbance at the potting stage as found with traditional methods growth is established rapidly. In some cases the whole process from sowing to sale can be completed within one season.”

Investigations into the effects of fertiliser levels, pot sizes and post planting performance of air root pruned ornamental species is continuing at CAFRE, Greenmount Campus.

For more information please contact Teresa Maguire tel 02894426694, or email teresa.maguire@dardni.gov.uk

Teresa Maguire (right), Horticulture Technologist at CAFRE, Greenmount Campus and Mr and Mrs P Smyth of Smyth Nursery, Portadown. With a three year old holly produced using air pruning technique.

Teresa Maguire (left), Horticulture Technologist at CAFRE, Greenmount Campus, with Richard Stevenson (Right) from Jiffy Products, UK,   with a 3 year old holly produced using air pruning technique.

Teresa Maguire, Horticulture Technologist at CAFRE, Greenmount Campus, with a three year old holly in 150 litres container produced using air pruning technique

Teresa Maguire, Horticulture Technologist at CAFRE, Greenmount Campus, with a three year old Cedrus deodara in 150 litres container produced using air pruning technique.