The present invention provides a cultivation system and a method for controlling the illuminance of the cultivation system. In the cultivation system of cultivated plants, the illuminance can be controlled to a more appropriate degree according to the state of the cultivated plants. The cultivation system includes: a sap flu detector (7), which measures the sap flow rate of the plants (2) cultivated in the house (3)； a shading curtain (5), shields the sun (4) from entering the house (3) The optical path of the light inside； and a control device that controls the opening of the shade (5) based on the sap flow rate.本發明提供一種栽培系統以及栽培系統的照度控制方法，在栽培植物的栽培系統中，可根據所栽培的植物的狀態來控制為更適當的照度。栽培系統包括：樹液流感測器(7)，對在房屋(3)內所栽培的植物(2)的樹液流速進行測定；遮光簾(5)，遮擋從太陽(4)入射至房屋(3)內的光的光路；以及控制裝置，基於樹液流速來控制遮光簾(5)的開度。
