Xil

Ir probably depends how yor lights are hooked up (in a wall outlet, or ran directly form the ac wires in your wall)

I've never grown so i'm not really sure how most are set up.

If its a plug in you can get ones made for lamps and most hardware stores, walmart, maybe walgreens, etc. pretty common item.
if its powered the other way could could probably still do it, youd just have to crack open one of those timers and do some wiring.

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