Nutrient management for protected ornamentals, bulbs and outdoor flowers


SummaryThe aim of this proposal is to improve nutrient management guidance for key crop types and growing systems within protected ornamental, bulb and outdoor flower production. This project will generate new information to update and enhance the ornamentals section of the AHDB nutrient management guide, and to support other knowledge exchange activities. It will deliver benefits to industry in the form of practical use guidelines, more cost-effective nutrient application and reduced risk of nutrient loss to the environment.  

Our approach is to undertake a short scoping study and consult with industry to identify the key issues and knowledge gaps within the sector. This will inform a dynamic and responsive 4-year research programme that includes: reviews of previous or ongoing studies; identification of best industry practice and innovation; observation and plant nutrient testing on commercial units; and new glasshouse and field trials.
The project will address areas relating to: delivery of nutrients to pot and bedding; managing feeding requirements of plants at different growth stages; nutrition within hydroponics; the effects of nitrate and ammonium as N sources; nutrient management for holding plugs and crate-grown lilies; nitrogen applications to narcissus bulb flowers; the role of nutrient deficiencies in primrose leaf edge scorch; and current and novel approaches to plant nutrient monitoring.
Industry involvement will be an integral part of the project, not only through consultation but also hosting and participating in the research, guiding project progress through the steering group, and commenting on the proposed new nutrient management guidelines.

Project code:
01 September 2018 - 31 December 2022
AHDB Horticulture
AHDB sector cost:
Project leader:


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About this project

Aim: Improve nutrient management guidance for key crop types and growing systems within protected ornamental, bulb and outdoor flower production


1. Undertake a scoping study and consult industry on the key issues and knowledge gaps for nutrient management for protected ornamentals, bulbs and outdoor flowers
2. Determine the effect of different factors (irrigation system, pot size and substrate type) on nutrition delivery in pot and bedding plants
3. Establish feeding requirements for different plant growth stages when using ‘one size fits all’ irrigation systems and plant growth regulators
4. Determine best practice nutrition delivery in hydroponics systems, including EC and pH specific to different crops
5. Investigate the effects of nitrate (NO3) versus ammonium (NH4) based fertilisers / plant nutrients on plant growth and quality
6. Determine best practice for managing groups of plants including i) holding plugs, ii) lilies in crates and iii) nitrogen application to field-grown narcissus in relation to stem length, base rot and NVZ restrictions
7. Reduce primrose leaf edge scorch through improved boron and calcium nutrition
8. Determine best practice for nutrient and plant monitoring, including imaging using infra-red or normal cameras
9. Use the information generated by the project to develop and improve nutrient management guidelines for the above areas, in order to underpin knowledge exchange activities and to inform updating of, and additions to, the AHDB nutrient management guide
10. Hold project management meetings, and provide annual and final reports in line with AHDB requirements