Turning purple

My outdoor plants turn purple or red. How can I do this inside? Does lowering the temperature work?
Seedz,

Internet

Plants of some varieties turn purple when temperatures dip down to the low 50's?F (12-13?C). Since the variety that you have been growing outdoors has this characteristic, you can induce it to change color by lowering the temperature of the grow space during the dark period. Bring the temperature down for several hours daily for about a week. Your plants will purple.

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