Modified humidity packaging of potted roses

Abstract

Wilting of potted plants in the distribution chain is a common problem in the ornamental sector. It is attributed to water loss by evapotranspiration – a process regulated by many factors including relative humidity (RH). Use of modified humidity packaging can be an option to reduce weight loss from potted plants by creating an optimal RH in the plant canopy. Different packaging configurations (bags and sleeves made from different packaging films) were developed and tested for potted roses. Packaged plants were first stored for 4 d at simulated transport conditions (16 °C, 86 % RH, darkness) then 7 d at simulated retail conditions (19−20 °C, 43–52 % RH, 12 h low light) and after that packaged plants were unpacked and stored for 6 d at simulated household conditions (19−20 °C, 43–52 % RH, 12 h low light). The packaging films were bi-axially oriented polypropylene (OPP), polylactic acid (PLA) and NatureFlexTM (NFX). Less water was lost by plants in bags than in sleeves made from same films and water loss was determined by the water vapor transmission rate (WVTR) of films. WVTR was the lowest for OPP bags and the highest for NFX bags. Due to guttation and leaf wetness in OPP bags, PLA bags were chosen for a validation test. Keeping potted roses in PLA bags for up to 11 days did not exhibit any negative effect on the keeping quality (leaf yellowing/wilting and flower/bud wilting) when compared to commercial OPP sleeves but the weight loss was reduced 2.6–3.8 times. Consequently, modified humidity packaging, and PLA bags in particular, is a promising alternative packaging solution for potted roses. However, further research is needed before this technology can be implemented.