In greenhouse cultivation, supplemental lighting is usually mainly applied during the winter, when outside radiation and temperatures are low. During this period the climate regime is determined mainly by growers: temperatures are determined and adjusted through the heating system. Paskal Systems however, recently conducted a study on the effects of the decrease in hourly growth influenced by small temperature fluctuation in a greenhouse with supplemental lighting. The data outcome of their Growth Analysis System provided the following findings:

A: Slight decrease in temperatures accompanied with slowdown in hourly growth.

B: Significant slowdown in temperatures is followed by a strong and sharp decrease in growth.

The sharp decline in temperatures is determined by the grower to balance the vegetative and productive performance. However, this case study indicates that the sharp decrease is a result of reduction in growth rate but also in plant weight loss (hourly growth below zero); a negative side effect.

It is possible to improve temperature strategy by following the growth rate under various temperature conditions with the help of Paska’s Growth Analysis System (GAS). The plant will respond immediately and results from the GAS will be available the following day, in order to optimize the climate strategy even further.