Effect of greenhouse heights on the production of aromatic herbs in Colombia. Part 1: Chives (Allium schoenoprasum L.).

Abstract

The tests were conducted in the municipality of Carmen de Viboral, 40 minutes from the city of Medellin (6º05'09"N and 75º20'19"W, 2.150 m a.s.l.). Three greenhouses with the same dimensions were used, with different channel heights of 2, 2.5, and 3 m, respectively. Temperature and relative humidity measurements were taken every 30 minutes for 3 years, and crop production was assessed. The aim of the study was to evaluate the effect of the height of the greenhouse on climatic conditions generated on a chives crop (Allium schoenoprasum). A multiple linear regression, colinearity analysis, and analysis of heteroscedasticity was performed to determine climatic variations caused by the difference in height between the greenhouses, and to determine differences in production levels. For statistical analysis, the SPSS software was used. The results indicate that, under the studied conditions, the greenhouse height directly affects the internal weather condition, reduction of 1 m in the minimum height of channel (from 3 to 2 m) resulted in an increase of minimum, average and maximum temperature by 0.37°C, 1.42°C and 3.56 °C, respectively, and consequently the chives crop yields, produced a 4.78% higher fresh weight of chives.