Soilless substrate science: A north american needs assessment to steer soilless substrate research into the future

Authors: FIELDS, JEB - Louisiana State University; Owen Jr, James - Jim; LAMM, ALEX - University Of Georgia; Altland, James; JACKSON, BRIAN - North Carolina State University; ZHENG, YOUBIN - University Of Guelph; OKI, LOREN - University Of California; FONTENO, K - Louisiana State University; SAMTANI, J - Virginia Tech; Campbell, Benjamin - Todd

Submitted to: Acta Horticulturae
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/19/2021
Publication Date: 8/20/2021
Citation: Fields, J., Owen Jr, J.S., Lamm, A., Altland, J.E., Jackson, B., Zheng, Y., Oki, L., Fonteno, K., Samtani, J., Campbell, B.T. 2021. Soilless substrate science: A north american needs assessment to steer soilless substrate research into the future. Acta Horticulturae. 1317:313-318. https://doi.org/10.17660/ActaHortic.2021.1317.36.
DOI: https://doi.org/10.17660/ActaHortic.2021.1317.36

Interpretive Summary: Sustainable production of specialty crops (i.e. fruit, vegetables, ornamentals, etc.) is becoming an essential component to feed and provide ecosystem services to the world’s population, and soilless culture can support that need. Many growers are beginning to transition many crops from in-field production practices to soilless culture. This is in part due to diminishing availability of fumigants, reduced availability of viable production land, increasing pest pressure, and the need for more efficient and flexible options. The objective of this research was to develop a North American needs assessment for soilless substrate research over the next 10+ years to support current and future users of soilless substrates and the suppliers that will support those users. Growers across all major specialty crop sectors were surveyed through an online poll, with select representatives of various specialty crop sectors participating in focus groups. This grower survey was then used to inform key interviews with substrate and allied suppliers in an effort to develop a holistic needs assessment for soilless substrate researchers to best support the soilless community. Results of this needs assessment showed that growers want to know more about their substrate, and what they can do with their substrate. The concept of “designer” substrates or custom blends to fit a specific purpose were highly regarded. Similarly, suppliers found education for growers and end consumers to be of high importance. Growers indicated the need for crop uniformity and increased quality as the primary reason to shift to soilless production or to limit the shift to soilless production. Conversely, uniformity among substrates, especially in concerns to quality control, is of the utmost importance. Minor variations in substrate composition and properties can result in major production differences. This consistency must be maintained and assured for growers to successfully transition to soilless production.

Technical Abstract: There is an increasing interest in transitioning conventionally soil-grown specialty crops (i.e. fruit, vegetables, ornamentals) to soilless culture. However, growers are often not fully aware of the opportunities, challenges, or measures to define success in adapting specialty crops to soilless systems. A North American needs assessment for soilless substrate science was conducted. The assessment consisted of three individual phases: 1) a North American grower survey with over 290 responses, 2) two online listening-sessions with twelve growers representing the diversity of North American specialty crops, and 3) one-on-one interviews with twelve substrate suppliers, processors, and distributors. The goal of this project was to develop a holistic understanding of grower and supplier needs with projections of increased substrate use in the coming years. The respondents were from a broad scope of growers, with 41% of respondents growing vegetables, 40% small fruit, 35% ornamentals, 30% tree fruit and nut, and 12% medicinal crops. It was determined that many high value crops (small fruits in particular) are transitioning into soilless culture, primarily as a means of disease control, have crops yield or finish earlier, and improving crop quality. Knowledge of the efficient use of resources, particularly in regard to water and fertilizer, and economic return on investment were identified by the participants as boundaries to adoption. Supplier interviews indicated that a transfer of trusted knowledge is imperative, and growers need support and evidence to initiate major changes. Suppliers believe that we must identify localized materials that are consistent, sustainable, cost-effective, and recyclable to support growers. North American specialty crop production is facing a transition period, as an influx of crops begin to transition to soilless culture. Connecting researchers, suppliers, and growers together to a new level can support all industries as we rise to the challenge of combating climate change and ensuring global food security.