Undergraduate sustainable learning: Effects of sustainable soilless media on production and sensory evaluation of cucumbers, basil, parsley, and lettuce

Modern greenhouse production has been ~100% reliant on fossil fuels for all inputs (glazing, heating, fertilization, lighting, post-harvest). Recent innovations may reduce fossil fuel dependence but their effectiveness may not be thoroughly tested. To promote education in sustainable production, undergraduate students in Greenhouse Management class (Hort 3002W; University of Minnesota) tested the effectiveness of two organic or 'sustainable' soilless media (Sunshine Natural and Organic Growing Mix, Sungro Metro-Mix Special Blend) with a control (Sunshine LC8 Professional) for crop production (height, leaf/flower number, yield) and sensory evaluations (appearance, texture, taste, purchase) of cucumbers ('Big Burpless Hybrid', 'Sweet Burpless Hybrid'), basil ('Opal Purple', 'Redleaf'), parsley ('Green River', 'Extra Curled Dwarf', 'Hamburg'), and lettuce (Flying Saucer 'Green', 'Red'). Significant differences between sustainable vs. control soils occurred for plant growth, depending on vegetative or reproductive traits, crops, and cultivars. These differences occasionally disappeared for sensory evaluation of edible components. In most crops, however, cultivars were highly significant factors. Undergraduate research can be used to provide directionality for future vegetable and herb plant breeding to focus on creating cultivars with increased yield and high consumer acceptance when grown in sustainable greenhouse soilless mixes.