Are they turning yellow?

Did you grow them yourself from seed inside? If you did and just put them out , yeah, without hardening off first, they would fry. It's too early to plant them outside. Mid May in this area is the earliest. I was reading in my journal last night, and recorded on May 12, 2008, "1/2" rain, Nor'easter, 40's temps. today. Coldest since 1800's".

If they're tomato plants you bought, and they were outside already, then it could be lack of water during this sudden un-seasonable heat.

Thanks,

I grew them from seed and they looked healthy. Now, most have died, just withered up. I just wanted them to get some sun. Guess I'll have to harden off the survivors, although I'm not sure how to do that.

Ok, good you still have some. Harden off by introducing them to the outside gradually, a couple hours the first day, 3 hours the next, increase the time a little more each day for about a week. At the same time , gradually introduce them to direct sun, an hour the first day, a little more each day thereafter. Make sure they're watered. Start off with filtered sun, as under a shrub that has leafed out. Since the ones you have left are weakened by the earlier stress, it will take a bit longer for them to turn around. When they look sturdy and dark green they'll be ready to plant in your garden.

carly,

Next year, try winter sowing your tomato plants. No need to harden off as they are always outside!

Actually, you might be able to try sowing a few seeds using that method for this year. Hop over to the wintersowing forum and check the FAQ's. A ton of info there.

Good luck!

Thanks Greengardener. I think I'm wintersowing everything next year. Did a couple containers of marigolds and petnunias in February and they're twice the size of the ones I started inside. And they're ready to plant. I showed them to my husband and he was so impressed he's talking about saving every milk carton or juice container that we can over the summer so we're ready to go when it gets cold.