frost and cold temperatures

lately in my area its been above freezing, literally 3-4 degree C at night. just wondering what is the lowest temp seedlings or small plants can handle without shocking them. just asking cause it seems like this year i dont got to wait till second week of june if the weather keeps going the same.

i know to gradually ease them into the cold/outdoor environment.

To be safe I wait until after Memorial Day to put them in the ground but here in Maine it can stillturn cold in May. I bring my seedlings in at night if it's getting below 40. Or put them in a cold frame.

Nova Scotia here, forgot plant outside again last night - seems fine.

Rule of thumb - plant 2 weeks after last frost

My recommendation is if temperature might be an issue at least germinate your seeds inside and get a set of leaves before you put them outside.

If that's not an option and you have to be outside from the get go, consider a large sized cooler ( or two ).

They can house alot of beer cups with seedlings or rooted clones. Comes in handy on chilly nights if you remember to close the lid. Helps to open the lid first thing in the morning too, don't fry them little ones! You can begin hardening them off, by leaving the cooler top gradually a bit more open at night. Now, a temperature controlled light bulb in that cooler, might even have your seedlings smiling in the micro climate oasis you can create.

Just as a point of interest I found this in my veggie garden. See attachment. Last year I took the soil from the pots that I grew in and dumped it in the tomato bed. The seed spent the winter there and sprouted this spring. I am in the Toronto area and the temps have dropped as low as 35F/1C.

did you have problems germinating seeds lsast year? its a great idea to put seeds in the freezer over night and then germinate them with some variaties.
should be interesting to see how she go's

My baby volunteer seedlings endured many nights of below freezing outside, and it's been as low as -4 or -5 C. They've been buried by snow a couple times, but seem to be totally healthy. Since days aren't getting much above 10 C lately, it's been growing very slowwwwwly.