Lighting device for plant growth

A lighting device for plant growth suitable for the growth of a plant, wherein the lighting device for plant growth comprises:

• a lamp having a light-emitting module on a bottom surface thereof;
• a lifting mechanism connecting a top surface of the lamp;
• at least two sensing mechanisms disposed at the bottom of the lamp, the sensing mechanisms and the light-emitting module having a longitudinal separation distance therebetween, each of the sensing mechanisms having a transmitter and a receiver configured with displacement, and a signal sensing path being formed between the transmitter and the receiver, wherein two adjacent transmitters having a distance of at least 10 cm therebetween;
• a control mechanism being coupled to the lamp, the lifting mechanism and each of the sensing mechanisms, and the control mechanism comprising a timing module, the control mechanism for activating or deactivating each of the sensing mechanisms according to a timed trigger signal generated by the timing module, when the sensing mechanism operating to form the signal sensing path and sensing the plant to generate a sensing signal, the control mechanism driving the lifting mechanism according to the sensing signal to control the longitudinal displacement of the lamp.