A spectrally adapted light emitting device for illuminating plants includes at least one semiconductor light-emitting diode (LED), at least one light conversion element for down-converting a portion of light emitted at the first wavelength to at least a second wavelength between 600 nm-680 nm, and at least one scattering device to diffuse light within the light emitting device. The at least one LED is configured to emit at least a first wavelength between 400 nm and 480 nm. The spectral light output from the spectrally adapted light emitting device is bi-modal with wavelengths in a range of 400 nm and 800 nm including a first local maximum between 400 nm and 480 nm and a second local maximum between 600 nm-680 nm with a local minimum between the first local maximum and the second local maximum.