Processors and Growers Research Organisation

Horticulture Strategic Centres for Field Vegetables

Summary: The strategic centres have core funding to give continuity in the variety evaluation trials for brassicas, carrots, onions and vining peas. These trials provide independent performance evaluation of yield quality, shelf-life and storage potential of the four crops and are the go to place for grower’s selection of varieties.

Additional funding for grower-led trials is split equally between the four crop groups to address/demonstrate solutions to the key issues for growers, either where there is a knowledge gap or an opportunity to demonstrate how research will translate into applicable technology. Crop group association R&D representatives are consulted ahead of each growing season to determine which topic will be addressed and how this can best be achieved.

Sector: Horticulture
Project code: FV 462
Date: 01 January 2019 - 31 July 2022
Funders: AHDB Horticulture with in-kind contributions from several horticultural growers
AHDB sector cost: £297,869
Total project value: £436,304
Project leader: Bruce Napier, NIAB; Angela Huckle, ADAS; Bill Herring, Duchy College; Becky Howard, PGRO


2019 Linclolnshire post-plant herbicide SCEPTREplus kale collards.pdf

2019 Lincolnshire aphid control on brassicas.pdf

About this project
The project aims to provide independent information for the grower on new vining pea, onion, carrot and brassica varieties.  For onions, this also includes storage evaluation. Open Days are held for each crop so that growers can see varieties growing in the field or harvested, as appropriate.

This project also provides the opportunity for grower-led demonstration trials.  The subject of trials for each crop are chosen annually by growers at their meetings.

All work packages are subject to consultation throughout the project to allow for changes in priority.

Core objectives:

Varietal evaluation

Vining peas – typically 15 – 20 varieties per year

Assessments : yield relative to a standard at TR105 and TR125, maturity relative to a standard at TR105 and TR125, size-grade specifications, haulm length, standing ability at harvest and disease susceptibility to downy mildew.

Assess frozen produce for colour (uniformity, number of blond peas) and Brix assessment for sweetness

Provide up to date information to growers in the form of the Descriptive List for vining peas, and via articles and publications in the horticultural press. Additional information will be communicated to growers via grower meetings and events, and via the PGRO website, the PGRO app, and the AHDB website

2019 - Vining peas: variety trial report

Onions – typically 35 varieties of onions per year

Sites:  a light sandy soil in Norfolk and a heavier silty soil in Essex both trials in commercial crops


Field records: emergence and vigour, leaf habit, fall-over (maturity date) and diseases when present.

Harvesting: The date when 80% fall-over (maturity date) has occurred should be recorded

Harvest records: graded yields, appearance, defects, quality and disease (typed where possible at grading)

Storage: Material from spring sown bulb trials to be stored with no sprout suppressant under ambient conditions and assessed on two occasions.  A sample of bulbs from the trials to be taken for storage tests. This will assess the relative performance of varieties in the absence of maleic hydrazide which is likely to become much more important for the future as restrictions on the use of sprout suppressants are introduced

Commercial storage: Nets with samples of selected varieties of onions, will be stored in a commercial box cold store

Data analysis: Data reported at harvest and post-storage

Carrots - typically 70 varieties of carrots

Site:  the trial will be within a commercial crop selected by BCGA each year

Trial layout:  blocked by breeder/seed company, single un-replicated plot per variety for demonstration

Plots demonstrated at the BCGA field event (usually first week in October) with nearby trade stands and marquee. Knowledge exchange at grower meetings and at the Carrot and Onion Conference.

2019 - Onions: variety trial report


The Carrot Demonstration Day, organised by BCGA in October is an annual event which is usually attended by over 200 visitors, exhibitors and seedsman - just about the whole UK carrot industry.  The event is an ideal opportunity for growers to bring themselves up to speed with the latest developments.

In 2019 there were 75 different varieties from 8 different seed companies, a selection tested for breakage characteristics. In addition to the trials there were trade stands showcasing products and services.

Trials data is not collected from the carrot variety trial, it is purely for demonstration to industry.



Variety trial hosted by commercial grower in Cornwall

Trials include autumn cauliflower, winter cauliflower, summer cauliflower and spring cabbage. Two planting dates are included, harvesting twice a week with weekly pest monitoring

In addition to the core cultivars, new confidential introductions will be recorded, as requested by the seed companies. This will encourage new cultivars to be tried and tested under local conditions

2019 – Brassicas: Cornwall brassica variety trials Cornwall

Grower-led demonstration trials

Vining peas

2019 – downy mildew control, biostimulants,  bean seed fly app and bean seed fly field trials

2019 - Vining peas: bean seed fly app report

2019 – Vining peas: biostimulant trial report

2020 – bean seed fly field trials, looking at the effect of cultivation timing before sowing

2020 – Vining peas: Bean seed fly cultivation trial report


2019 – sowing density trials to fit in with supermarket size specifications

2019 – onions: onion density trial report

2020 – herbicide trials testing useful products coming out of SCEPTREplus


2019 - seed size v drill depth trials and breakage testing of selected varieties compared with industry standard variety Nairobi

2019 – carrots: carrot varieties, seed size v sowing depth trial and carrot breakage trial

2020 – sowing density trials, seed treatment comparisons, more detailed root breakage testing


2019 – Lincolnshire - insecticide screening for aphid control options, pre-and post-planting herbicide screening of promising products from SCEPTREplus

2019 – brassicas: Lincolnshire aphid control on Brassicas

2019 – brassicas: Lincolnshire pre-planting herbicide SCEPTREplus kale and collards

2019 – brassicas: Lincolnshire post-planting herbicide SCEPTREplus kale and collards

2020 - Lincolnshire - post planting herbicides on kale and collards and evaluation of treatments for storage cabbage

2020 - Scotland – testing of pre- and post-emergence herbicides, testing of promising herbicides from SCEPTREplus, systemic downy mildew and biostimulants. A film has been produced to give an overview of trials activity

Monitoring of brassica pests such as diamondback moth and swede midge is also taking place at several Strategic Centres and is reported in the AHDB Pest Bulletin