When is it too cold to bother with a freeze warning?

[BradinMichigan]

Hello everyone I'm here in Southeast Michigan. We are supposed to have a record cold tonight 25 degrees Fahrenheit in the forecast! A huge WTF this late. My question is is there a temperature where it's just too cold to even bother covering up plants with sheets and paper bags? I've got many perennials that are already getting big spring Growth due to our wonderful warm weather that we've had. I've got zero mulch down besides the last fall leaf and grass litter. I think I've pretty much accepted the fact to let mother nature do her thing and whatever will be will be. Although, part of me wants to make sure I get the blooms this year and another part of me is just like yeah no just roll with it. From what I've read covering plants kind of only make a 2.4 degree to possibly 9 degree difference. I guess my question is is 25 a to hell with it and freeze temperature and it probably won't help?

Frustrated with the world today!

 

[karstopography]

Forecasts can be wrong. A few degrees off then you are at 30 rather than 25. Maybe the wind shifts and that moderates the weather. 2-3 hours at or below freezing rather than 8-12 hours is a big difference. Look at what your plants are and what they can handle and how each set up for freezing weather and then make an effort to save which ones you can or care the most about. Some plants might be more expendable than others, but it‘s amazing what can be done in a short amount of time to give plants the protection they need.

We get cold snaps in the winter that “should“ have killed this or that tender plant just based on the forecast, the length and depth of the cold, and the plant, but a little freeze cloth saved the plant. 25 degrees doesn‘t seem like you should completely throw in the towel and give up.

 

[Chuck]

The actual time of below 32F makes a big difference. 25F isn't all that bad if it doesn't last very long. There is a product you can get at most BBS and all nurserys called NSulate. It will give you 6 degrees of protection.

 

[phoenixangel429]

The actual time of below 32F makes a big difference. 25F isn't all that bad if it doesn't last very long. There is a product you can get at most BBS and all nurserys called NSulate. It will give you 6 degrees of protection.

I have a similar situation. But here in Kentucky they're calling for around 28-30 tonight and 32-34 tomorrow for lows. It has been raining all day too and I read that this may actually help. Is this true?

 

[Chuck]

I have a similar situation. But here in Kentucky they're calling for around 28-30 tonight and 32-34 tomorrow for lows. It has been raining all day too and I read that this may actually help. Is this true?

The rain will help somewhat but it won't be much help if the Temps stay below freezing for very long

 

[DirtMechanic]

Water absorbs a lot of heat. Its a mass thing. A cubic yard of dry soil has less molecules than a cubic yard of wet soil. If all those molecules in wet soil are at an above freezing temp, then the cold molecules of very much less dense air gases take even longer times to exchange energy. Covering actually traps the existing heat of the earth in this case, and protecting from convection of cold air is also part of the plan. Moisture bearing cold air is the worst for the same reasons. If its a dry air mass then that is actually helpful as less energy is available to transfer because the air is less dense than moist air.

 

[Fractal Farms]

I have a similar situation. But here in Kentucky they're calling for around 28-30 tonight and 32-34 tomorrow for lows. It has been raining all day too and I read that this may actually help. Is this true?

Yes, most frost damage is from dehydration. Water prevents them from getting freeze-dried.