Liagh Whelehan - Nuffield Ireland

Liagh Whelehan, Horticulturalist, Wexford

Liagh grew up on a dairy farm in Laois, later moving to a dry stock farm in Wexford. She spent her formative years outdoors, in the fields, woods, or vegetable gardening, developing a deep and lasting passion for the natural world. As part of her Nuffield Scholarship. Liagh will investigate methods of improving efficiency and sustainability in plant propagation in controlled environments. Liagh holds a BSc and an MSc in Business Management from UCD. Her studies gave her a grounding in environmental issues and biology, but also taught her the realities of operating in a commercial world. Horticulture was an obvious career choice, as growing plants has been a passion since childhood, and she currently works as a grower and assistant production manager in a bedding and pot plant nursery in North County Wexford.

Liagh’s Nuffield report is ‘Sustainable plant production in controlled environments’

Executive Summary:

This research aims to examine the commercial viability of sustainable horticultural practices in controlled environment crop production with regards to new growing technologies and alternative approaches. This is with a primary focus on increasing the efficiency of young plant production (both seed and cutting raised) and the methodologies to do so in the context of an ever more challenging production environment. These include but are not restricted to policy and regulatory changes, fluctuating consumer demands and market trends, labour availability, climate change and economic factors such as rising input costs. Many of these are global issues and as such we have much to learn from our international counter parts.

Teagasc valued horticulture, the fourth largest agricultural sector in 2023 at 521 million euro (farm gate value). Within this controlled environment agriculture contributes both produce for direct human consumption, plants for growing on in field production and plants for amenity usage. Post covid saw a sizable increase in consumer spending on garden related purchases, from woody shrubs and bedding plants to houseplants. Many of us experienced the now well documented mental and physical health benefits of engaging in horticulture during the covid lockdowns of the 2020s and considerable health benefits have been associated with engagement with green spaces.

Key recommendations:
Recommendations need to be considered in the context of the type of system being examined – extensive or intensive. Approaches to growing “cold, slow and low or hot, fast and high”. In controlled environments, growing crops with shorter programme times to optimise space and time requires higher inputs. This increases crop value and volume but also the overall cost of production. The opposite end of the spectrum is growing “slow and cold”, with lower inputs but reduced turnover. Two different approaches dependant on infrastructure, available resources and the crop in question.

During this study 11 countries were visited including, New Zealand, California, Japan, Belgium and The Netherlands. In each, discussions with growers, breeders, government representatives, research agencies and industry suppliers informed the recommendations below. These are equally applicable to finished or young plant producers or systems combining the two.

1.The precision/ targeted usage of inputs to maximise crop results while minimizing costs.

Fertiliser formulations, application methods and usage
Water collection and delivery systems
Energy consumption (e.g. supplemental lighting, heating etc)

2. More targeted crop selection (within the context of meeting market demands)

To optimize return per square meter based on crop value
To reduce “downtime” between crops (particularly important in the context of intensive systems)
Taking environmental changes and pressures into consideration e.g. heat stress, moisture requirements etc (Increased flexibility improves climate resilience).
Location/ condition specific genetic suitability

3. Greater engagement with non-chemical solutions to reduce dependency on pesticides (Integrated Pest Management (IPM), environmental manipulation etc)

As alternative pest control methods
For disease mitigation
As Plant Growth Regulator (PGR) alternatives

4. Technology, not a dependency but a partnership – for improved production efficiency and less labour dependant systems, effectively reducing long term production costs and improving overall efficiency of systems.

5. There needs to be innovative thinking for practical problem solving, unique solutions for unique situations. To draw a picture, Controlled environment agriculture (CEA) is not a clear field, a fresh start after ploughing, it’s tunnels, glasshouses, warehouses, combinations of all three in a huge range of configurations. This restrict homogonous approaches to crop production and requires solutions more tailored to individual sites.

6. Collaboration within the industry, a highly competitive domestic market often disincentivises information sharing. However, a collaborative mindset was observed from the Netherlands to New Zealand actively benefitting agricultural communities in a variety of ways from improved production outcomes to general industry and personal resilience.