Not sure where you are, but here in Southern Indiana, regardless of what the forecasters are saying, we covered up sensitive plants (we have tomatoes in raised beds already, tree peonies etc.) last night and will do so again tonight. Forecast for the "greater Louisville" area is a low around 38 but we've found we get temps a good 5-8 degrees colder than that north of the river. Jonathan FWIW Most weather forecasts are for about 6ft above the ground, Normal instrument height.. At ground level it might be 6 to 12 degrees colder, The number us plant growers need Actually I'm in NH, about 2 USDA Zones colder than Jackson Co. ( been there) Actually colder than Fairbanks, Alaska LB