How long until I can move these outdoors?

Ok well I took 5 of the seeds I was soaking in water and planted them into plastic cups. Questions.. How big should I let them grow in these before moving them outdoors? Also.. I can keep them inside but I dont know if I have correct lights for them.. I have one of those desk lights with an arm I could hover over them but that's only like 75 watt's. I could get another light as well but probably only 75 watt's at the most. I do not want to fully grow them inside, will makeshift lighting work inside?

you can let them grow until 6in to 8in before you set them out. set a fan rotating on them to build up the stems , so when you do set them out, a good gust of wind wont knock them over.