How much should I drop temp at night to bring out purple?

Hey, I was torn between white widow, rasepberry cough, and the NYPD on nirvana and finally settled with the rasepberry cough.

As some of you may know this is a strain with hints of purple. I read you have to bring it out by dropping temp at night..

Anyone here know by how much? Anyone ever grow this before? I got a few days before I get some cash so I got plenty of time, just need an answer. Thanks!

I wouldn't drop temps just for a purple effect, getting the most yield is more important imo. But if you must, drop it into the 50s and lower the (P).

I just lower temps and keep on pushing heavy nutes. Here is some Sour Kush with temps going as low as 55 at night and 78 day.

temps should be like 55-60 with a fan on at night alot