Development and performance evaluation of vertical farming structures in rainshelter

Abstract

A study was conducted to develop a vertical farming structure suitable for rainshelters for homestead cultivation of Kerala and to evaluate the performance of the developed structure. The newly designed and fabricated Vertical Farming Structure (VFS I) was compared with two existing structures, viz, VFS II and VFS III. Amaranthus of CO-1 variety was selected for the study. Combination of Sand: Soil: Cowdung: Vermicompost in the ratio 1: ½: 1: ½ respectively on volume basis was selected as the growing media. Irrigation was provided through drip irrigation. The performance of the vertical farming structures was compared by assessing the climatic parameters (temperature, RH, light intensity and PAR) and biometric observations (height and number of branches) and yield. Maximum temperature (37.28°C) was recorded during 1:00 PM and lower temperature (24.1°C) was recorded during early morning hours. Higher relative humidity (98.9%) was recorded during early morning hours and lower relative humidity (50.59%) was recorded during afternoon hours. Light intensity and PAR were maximum in VFS I (49000 lux and 1032 µmol m-2 s-1) followed by VFS II and VFS III respectively. Statistical analysis was done by twoway Analysis of Variance (ANOVA) with replications using SPSS 16.0. The results from statistical analysis showed that the light intensity and PAR at 8:00 AM, 1:00 PM and yield per plant showed a significant difference between the structures and tiers individually and also in combination at 5% level of significance. Light intensity and PAR at 5:00 PM, height and number of branches significantly varied between structure and tier individually. Maximum B-C ratio of 1.33 was obtained for VFS I, followed by 1.19 and 1.13 for VFS II and VFS III respectively. The positive values of NPW in all the three cases indicated that the project is viable. The overall results of the study revealed that the VFS I showed better performance in all aspects compared to VFS II and VFS III. The study recommended rainshelter cultivation of vegetables with facility for utilising vertical space using the vertical farming structure and drip irrigation. The developed structure is suitable for increasing the production from the homesteads of Kerala.