Quote Originally Posted by jwmsalisbury
The highest I could find at the grocer store was this 23 watt, 1600 lumens CFL. What does it mean when the packaging says Day Light 5000K?
It looks so much brighter than before!

There are different K readings for different lamps. Daylight is for Veg stage. Red color is 3000k to 2700k and is for flowering. The plants like certain kinds of light at different stages.