If they are going in the garden in 3-4 days, they should NOT be inside under lights now. They need to be hardened off, that is gradually acclimatized to the bright outdoor sun, wind, temperature variations, etc.
Here's one thread about hardening off: viewtopic.php?f=4&t=68026&p=385243&hili ... ff#p385243
I do it not by increasing hours per day of sun (as some people do), but by increasing exposure. When I first bring tender plants out, I put them in a very protected spot where they get no direct sun or wind. Once they've been there for a couple days, I move them to a place where they have some exposure to filtered light or early morning sun. Then I gradually increase sun exposure until they get to the level they are going to stay at. Then they can go in their garden spot. If you are still having very cold nights, you may have to bring them in at night for awhile.
So if you want to plant them soon, you need to be hardening them now! Depending on how much different outdoor conditions are from indoors, hardening may take anywhere from five to ten days. You will know if you move them to a new location (or extend their sun hours) and they react by wilting, curling their leaves, getting sunburned edges, etc., they weren't ready forthat much exposure and you need to slow the process down.