Warm white light can indeed be beneficial for plants, particularly when targeting specific growth phases like flowering.
According to guidance on plant lighting, the suitability of warm white light depends on the plant's current stage of development.
For the initial phase of vegetative growth, where plants are primarily focused on developing leaves and stems, a 'cool white' lamp is typically recommended.
However, when plants enter the flowering stage, warm white light proves more effective. The reference explicitly states that "a 'warm white' light will be better [than cool white] as it is stronger in the red end of the spectrum which is more suitable for flowering."
The higher concentration of red light in warm white spectrums plays a crucial role in triggering and supporting the development of flowers and fruits. Different wavelengths of light influence different plant processes, and red light is particularly important for reproductive stages.
Here's a simple comparison based on the provided information:
| Light Type | Recommended Primarily for... | Key Spectral Characteristic (as per reference) |
|---|---|---|
| Cool White | Vegetative Growth | N/A (Reference doesn't specify its spectrum) |
| Warm White | Flowering | Stronger in the red spectrum |
Therefore, while cool white is preferred for leafy growth, warm white is specifically considered good, and even better than cool white, for encouraging plants to flower due to its rich red light content.
