Improving weed control in hardy nursery stock



With the loss of key herbicides available to the HNS sector, weed control has become critical. Recent projects CP86 , HNS/PO192 and 192a have identified promising new products in screening trials although some have limitations.  A programme of work is planned to build on these findings and fill gaps in control.

Starting with a review of weed control practice in relevant countries, identified herbicide candidates will be assessed for activity against key weeds in container HNS with pot trials to determine control at pre-emergence and early post- emergence.  Phytotoxicity to indicative HNS species, in growth and dormant, will be screened at ADAS Boxworth.  Promising materials will be taken forward for on-nursery trials.

The field-grown HNS sector is now over-dependent on few herbicides.  New products have already been identified with potential for use in field-grown herbaceous, roses and trees. Field-trials will be carried out utilising novel products with existing herbicides to develop improved programmes.

Differential band-spraying developed for vegetables in SCEPTRE has potential for use in tree seed beds and will be investigated in nursery-based experiments.

The HDC ornamentals weed research programme has been successful.  This proposal will continue this work, ensuring growers have the weed control techniques for the future. 

Project code:
HNS 198
01 January 2016 - 31 December 2020
AHDB Horticulture
AHDB sector cost:
Project leader:


HNS 198_Report_Annual_2017_0 HNS 198_Grower Summary_Annual_2017 HNS 198_GS_Annual_2016 HNS 198_Report_Annual_2016 HNS 198_Report_Annual_2018 HNS 198_Grower Summary 2018 HNS 198_Report_Annual_2019 HNS 198_Grower Summary_Annual_2019

About this project

Aims and Objective:


To improve weed control in hardy nursery stock by means of chemical, biopesticide and cultural approaches.


1.   To review chemical and cultural weed control techniques used in other countries on hardy nursery stock focusing on chemicals and techniques that have potential to be employed under UK conditions and regulations.

2.   To measure novel herbicides efficacy for key nursery stock weed control in pot screening experiments.

3.   To assess novel herbicides for phytotoxicity in initial screens on indicative nursery stock species, then evaluate and demonstrate on commercial nurseries the most promising novel products in phytotoxicity screening on a wider range of container grown nursery stock.

4.   To quantify the effectiveness and safety of selected novel herbicides when used in two season programmes for budded rose and tree production systems.

5.   To evaluate a range of novel herbicides for use post-planting for selected field grown herbaceous crops.

6.   To critically evaluate novel technologies for improving weed control on nurseries.

7.   To provide support for AHDB’s EAMU programme for herbicides in ornamental plant production.

8.   To deliver appropriate knowledge transfer outputs that will include updates via social media, briefing notes, growers’ walks and workshops, study tour and content for updating the Practical Weed Control for Nursery Stock guide.