The freeze could kill or damage plants that have bloomed in the last few weeks.
Parkview Gardens, a nursery in St. Charles, has been selling plants outside over the last several weeks. The outdoor tables were empty and plants were inside Monday night in preparation for the freeze.
"If Mother Nature gives me an in and lets me fight, I'll fight," said Tom Goeke, owner of Herman's Farm in St. Charles.
He cannot bring his apple or peach trees inside, trees that already faced a threat over the weekend.
"Because we dodged that bullet, now we're actually using that situation to help the next situation which is going to be 18-22 degree temperatures on Wednesday morning," Goeke said.
Peach and apple trees are kind of like St. Louisans when winter will not go away for good, they have to toughen up a little bit.
"Yesterday these [peach blossoms] were all open and beautiful but what's happening and this is a good thing, they're closing back up," Goeke said.
If the temperature stays around the mid-20s, Goeke can spray water on the buds, increasing their chance of survival.
"By spraying that water, there is a term, and what it does is when water melts and freezes off and on it causes an energy [transfer] and raises the temperature maybe two degrees and it's everything," Goeke said.
If it gets too cold, Goeke will simply lose the crop.
It has happened before, and he said it is like losing a family member.
"You can't equate Mother Nature into it," Goeke said. "You think you should have done something better, it's just kind of the way you feel. It's a human nature thing."
Goeke's tip for protecting outdoor plants at home is to put them under a sheet or blanket. He also suggests putting a fan under the blanket to get air moving.