The company was brought in last autumn to tackle the Regent's Park and Primrose Hill knotweed problem. After its successful eradication, assistant parks manager Andy Williams has asked the firm back to help staff with future outbreaks.
"We have been delighted with JKC's approach to managing the knotweed problem as well as its willingness to work with our grounds and gardens staff on this issue. Increasing overall awareness, understanding and investment in training will deliver significant, longer-term benefits for Regent's Park and Primrose Hill and potentially all of our Royal Parks."
JKC's stem injection system works by injecting Glyphosate herbicide directly into the knotweed stem, allowing "maximum control with minimal impact on the surrounding vegetation and the environment", Williams explained.
He said environmental impact was a vital consideration for Royal Parks because of the risk posed by traditional foliar applications to the parks' plants and gardens.
"We were impressed with the ease with which we were able to engage JKC in the application process and the way it listened to our very specific needs and developed a bespoke treatment programme that met all our objectives," he added.
The contract was awarded following JKC's successful treatment at Greenwich Park and it included work on 19 infestations across the 116ha Regent's Park and one in Primrose Hill.
The company will now carry out training sessions with the grounds maintenance contractor's 45 gardening staff, highlighting awareness and identification of Japanese knotweed as well as other invasive, non-native weed species.
A smaller number of gardeners will be specifically trained in the stem injection system so that longer term Royal Parks can invest in the applicators and carry out ongoing treatment in-house.