Nothing special. Have you transplanted seedlings yet? Usually three to four inch containers are sufficient until you get them outside. You are in the same zone as myself, and I used to start taking them outside (in shade initially) middle of May during the day to harden them off. I use a greenhouse now, so I do this earlier, but as far as indoor prep, just make sure to keep them healthy in appropriate pots, with a fan. If you are running a long light cycle (18-24 hours) you can start reducing the light cycle to more closely match sun cycle at your harden off time as you get closer, but it's not really necessary in my experience.

Have you properly prepared your outdoor bed that you plan to plant in? Good time to mix compost in your soil.

Thanks for the info. I guess what my problem is I did too many plants and will probably be too difficult to move all of them in and out everyday. In retrospect I shouldn't have done so many.

The cycle of light is 12 hours per day, which what I thought in our time zone would be about the same when I plant them outside. Does that sound right to you?