CTT in Kelvin (K)/ Light Color/ Effect/

5000 to 8000/ Deep blue/ Encourages excellent leaf and stem growth.

4000 to 5000 / Light blue/ Encourages good leaf and
stem growth.

4000/ Neutral white/ Promotes normal growth.

3700 to 4000/ Warm neutral/ Promotes rapid growth.

3000 to 37000/ Warmer yellow neutral/ Highly active
photosynthesis for all stages of growth.

1500 to 3000/ Hot orange or red/ Promotes flowering

For cannabis, 6500k is the ideal spectrum for vegetative growth. Now this doesn't mean the plants wont grow under other specs, it just means they will do best at 6500k. in flower, cannabis does well with warm specs, 2300-2800k is ideal for maximum bud production, where as 6500k will grow shorter more dense plants with more leaves, tighter node spaces.