They'll most likely be fine but just won't grow. Once the ground warms up they'll probably take off but all I meant above was it's kind of a waste of time planting them into the ground now, seeds or plants directly planted. Cool temps on the roots will stop growth, not kill them, that's all I was trying to say. And ground temps below 50 will stop or at least greatly hinder growth so all the little seedling will do is sit there waiting to be chomped on. Which is another reason why seeds should be started indoors. Until they build up a thicker "skin" they're very susceptable to leaf cutters and other insects (even birds will pull out the seedlings) so I like to give them a month's head-start inside before setting them free.

But if you must plant a seed directly into the ground then at least make a barrier to keep out the small critters and give it that one month grow period to get stronger. A barrier can easily be made out of an aluminum can by using a serated steak knife or similar and cut the ends off of the can then center over the seedling or seed site and press gently but firmly into the ground just enough so it won't blow away. This will keep away most small critters that give us fits so often during the critical seedling period...I mean how often have we gone out to check on our just-sprouted seedling only to find a tiny little stump is all that's left? Yup, leaf cutters (not the leaf cutter ant or bee) in action and they're everywhere!

Just trying to help you guys be more efficient.