The charts on this page show the probabilities of receiving a certain temperature on a certain day. Some examples that might help:
|First 16°||Oct 27||Nov 2||Nov 6||Nov 10||Nov 14||Nov 17||Nov 21||Nov 25||Dec 1|
|First 20°||Oct 25||Oct 30||Nov 2||Nov 5||Nov 8||Nov 11||Nov 13||Nov 17||Nov 21|
|First 24°||Oct 14||Oct 20||Oct 24||Oct 27||Oct 31||Nov 3||Nov 6||Nov 10||Nov 16|
|First 28°||Oct 1||Oct 6||Oct 10||Oct 14||Oct 17||Oct 20||Oct 23||Oct 27||Nov 2|
|First 32°||Sep 20||Sep 25||Sep 29||Oct 2||Oct 5||Oct 8||Oct 11||Oct 14||Oct 20|
|First 36°||Sep 16||Sep 19||Sep 22||Sep 24||Sep 26||Sep 28||Oct 1||Oct 3||Oct 7|
What's a safe temperature for tender plants? When the nightly temperature falls, frost can form, even above 32°, because the air is colder high above the ground and the frost can form up there and then fall down onto your garden and do some damage, even if it's 36° on the ground. So many factors come into play, including wind, concrete, houses, trees and other structures, etc etc etc. Because of all this, you might want to consider 36° as "the danger zone".
In your average springtime, you have a 90% chance that there will be no 36° nights by May 24. In other words, you can pretty much count on being safe from frost by that day. But we want to get those tomatoes in the ground as soon as possible, right? We see that there's still an 80% chance of 36° on April 30, so we don't dare plant that early. We wait a few days and by May 10 we are at the 50/50 point. At this point, we are close and we can start watching the weather forecast. If the upcoming week's forecast doesn't show below 40°, then it's probably okay to risk planting out your plants. If conditions change and a surprise frost does threaten, there's always things you can do to protect plants from frost.
|Last 16°||Apr 2||Mar 29||Mar 25||Mar 23||Mar 20||Mar 17||Mar 14||Mar 11||Mar 7|
|Last 20°||Apr 10||Apr 6||Apr 3||Mar 31||Mar 29||Mar 27||Mar 24||Mar 21||Mar 17|
|Last 24°||Apr 17||Apr 13||Apr 11||Apr 8||Apr 6||Apr 4||Apr 2||Mar 30||Mar 27|
|Last 28°||Apr 28||Apr 24||Apr 21||Apr 18||Apr 16||Apr 13||Apr 10||Apr 7||Apr 3|
|Last 32°||May 12||May 8||May 5||May 2||Apr 30||Apr 27||Apr 25||Apr 21||Apr 17|
|Last 36°||May 24||May 19||May 15||May 12||May 10||May 7||May 4||Apr 30||Apr 25|
Now that you know your frost dates, use our Garden Planting Calendar for Minneapolis to know when to sow and transplant your various vegetable plants!