Comparing compact pepper growth under LED lights and sunlight
In 2019, US sales of edible and ornamental pepper (Capsicum annuum) plants for the home gardening market were valued at $38.5 million and $1.7 million, respectively. Edible pepper is followed only by tomato (Solanum lycopersicum) and culinary herbs as the most popular vegetable-type bedding plants sold in the United States. Home gardeners who grow peppers for edible use often prefer high-yielding and disease-resistant plants, whereas those who grow them for ornamental purposes prefer small plants with colorful fruit that maintain visual harmony within the landscape.
There are numerous new compact pepper cultivars available that can be grown as potted, bedding, or garden plants. Most compact ornamental peppers produce pungent fruit of different shapes and colors. Although pungent peppers are increasingly becoming popular among US consumers, they are frequently used as processed products. In contrast, sweet peppers are frequently consumed fresh, but only a limited number of compact cultivars are available in the market to date. Regardless of type, compact pepper plants offer a space-saving advantage that can be particularly attractive to urban dwellers interested in gardening in small spaces such as window sills, patios, or balconies.
Increasing migration to urban areas with limited outdoor space has also spurred interest in indoor vegetable gardening. However, few studies have been conducted in support of this increasingly popular gardening trend. Understanding the requirements to grow compact fruiting vegetables like pepper indoors is key to support the urban consumer and could help advance existing efforts aiming to increase the availability of plants grown by the commercial indoor farming industry.
The objective of a new study appearing in HortTechnology was to compare growth and productivity of 14 compact pepper cultivars grown in two environments. A greenhouse was used to evaluate plant responses under sunlight and in a fluctuating climate, close to outdoor gardening conditions. An indoor growth room was used as a proxy to a residential space with a constant daily light integral (DLI), and moderate temperature and relative humidity (RH). We also aimed to compare intumescence susceptibility among the different cultivars.
Plants in the greenhouse were generally larger in size and produced a greater fruit yield than those grown indoors. All cultivars evaluated in this study are recommended for container gardening under sunlight, as their growth and yield are likely to satisfy the average home gardener. Similarly, all pepper cultivars are likely suitable for indoor gardening due to their compact size, but CO, PN, and YT produced the lowest total fruit fresh weight per plant, and thus should not be recommended to consumers aiming to maximize fruit yield.
Cultivars CA, CH, HTR, PN, SJ, and SY were affected by intumescence, which could negatively affect indoor gardening experiences until recommendations to mitigate the disorder become available for small-scale gardening applications. Considering that the highest-yielding cultivars in both environments were generally the largest plants, home gardeners aiming to maximize yield should produce the largest cultivar that can fit within their designated growing space.
More information:
Stephanie Cruz et al, Evaluation of Compact Pepper Cultivars for Container Gardening Indoors Under Light-emitting Diodes and in a Greenhouse Under Sunlight, HortTechnology (2023). DOI: 10.21273/HORTTECH05194-23
Provided by American Society for Horticultural Science