Effects of frost on tomatoes

[tnpeppers]

Out of the blue; the weatherman has dropped a 'Frost Advisory' on my area for tonight...temperatures expected to run around 33 to 37. Naturally; I will be picking anything ripe or even blushing. What about the tomatoes that remain? If the plants get nipped at the temps indicated above; does that kill the green fruits that remain? There are still loads of green Casino Chips and Ambrosia Reds out there (among others) that would ripen if they had another two weeks. I am trying to see if I can score a 24 x 30 tarp to put over them tonight, but no luck yet.

Normally, the first, light frost doesn't hurt much in my garden if it doesn't last all night. It might burn a few leaves on the outer portions of my tomato plants but any fruit under the protection of foliage isn't damaged. Normally within a week or so, a heavier, longer frost will do more damage and then a freeze will kill everything. That typically doesn't happen until mid to late November.

Ted

[Doug9345]

The 37°F wouldn't concern me, but the 33°F would. Almost anything will work to save a plant from a light frost. Old sheets, taped together news paper, that sort of thing. You only have to buy a degree or two for a couple of hours. They are calling for frost in some areas here. I think it will miss us, too wet here.

The other thing I've found out is don't wait until dark to do cover them. I've done it as early as 2:00pm. I'd certainly have them on by 5:00PM.

[tnpeppers]

Haven't heard that advice about covering early before...certainly can't hurt...thanks!

[Durgan]

Frost seriously damages tomato fruit. The morning after a frost the fruit appears to be fine, but it rots quickly where the frost has damaged the skin in patches.

The best way to utilize all those green tomatoes is to pick them and eat them fried in a bit of butter. They should remain in good shape for about a month.

[carolyn137]

Originally Posted by Durgan

Frost seriously damages tomato fruit. The morning after a frost the fruit appears to be fine, but it rots quickly where the frost has damaged the skin in patches.

The best way to utilize all those green tomatoes is to pick them and eat them fried in a bit of butter. They should remain in good shape for about a month.

Durgan, the degree of damage is dependent on how heavy the frost is, as to temps, and how long it lasts, so just saying that frost seriously damages fruits is something I can't agree with.

It also helps if you have a weedy tomato patch since the weeds, usually tall in the Fall if not removed earlier, get hit first and thus protect the tomato plants.

And the advice to never use any plastic covers is good as well. The inner side of the plastic builds up condensation and when that freezes the plastic sticks to the plants and fruits and can cause even more damage.

Carolyn, who remembers when growing up on the farm that if frost was expected, especially in late Spring, her father would take lots of old tires to the fields , put them in piles and set them on fire. The black residue would land on the foliage and serve as ice nucleating particles,not known by that name back then, thus protecting the foliage.

"Carolyn, who remembers when growing up on the farm that if frost was expected, especially in late Spring, her father would take lots of old tires to the fields , put them in piles and set them on fire. The black residue would land on the foliage and serve as ice nucleating particles,not known by that name back then, thus protecting the foliage."

The EPA would quickly arrive with a swat team and black helicopters if you tried that today. You would be sorting and saving your tomato seeds in a jail cell.

Ted

[carolyn137]

Originally Posted by tedln

"Carolyn, who remembers when growing up on the farm that if frost was expected, especially in late Spring, her father would take lots of old tires to the fields , put them in piles and set them on fire. The black residue would land on the foliage and serve as ice nucleating particles,not known by that name back then, thus protecting the foliage."

The EPA would quickly arrive with a swat team and black helicopters if you tried that today. You would be sorting and saving your tomato seeds in a jail cell.

Ted

Don't I know it Ted, but if jail was up here where I am now the jail food isn't all that bad and I should know b'c the meals on wheel lunches that I get are prepared at the jail and the inmates do some of the prep work.

And I first found out about ice nucleating particles when I was in Denver in the 70's and the Chairman of the Microbiology Dept had received a grant, I think from the Federal Govt to work on it as he had proposed. His name was Dr. Lloyd Kozloff and I'll link to a Google search for him and his work, but first let me link to a Google Search on ice nucleation in general as it related to frost protection.

https://www.google.com/#q=ice+nuclea...ost+protection

And now to Kozloff's work with it:

https://www.google.com/#q=Kozloff+ice+nucleation

Kozloff moved from the Med School in Denver to become the Dean of the Grad School at the U of California, so that's why some of the links refer to his continued work there.

It's been used successfully for the many acres of Strawberry fields in CA, and I certainly didn't read all the links where it's been successful for frost protection.

Carolyn

[Labradors2]

Well if they are burning tires in CA to keep their strawberries from getting frost-injured! , that's another good reason for not buying/eating those awful things!

Linda

[KarenO]

Frost is something I know about. Tomatoes, if covered well with blankets/sheets can survive a couple degrees of hard frost. unprotected plants will be severely injured and fruits exposed, even ones that look OK initially will not keep and if green, generally will not ripen. I watch the forecasts and if real frost threatens, I pick what cannot be securely covered and allow them to ripen indoors. It's a yearly ritual here in my zone 3a garden. We are doing well in my area so far with no frost in sight just yet so mine are all still out there and ripening beautifully on the plants this year so far. I will have greenies to ripen indoors at the end of it all but not as many as other years with early frost. It's been a very good year for me up here with even the later varieties having a chance to ripen on the vine.
KarenO

[Labradors2]

Karen, you are lucky!

Here in Kingston we had a frost warning last night so I picked everything that I could, including all the melons. This morning the roofs were frosty, so it was probably just as well that I did, although only one tomato plant showed signs of being hit by frost - wilted leaves......

Linda

[cythaenopsis]

Do the cooler temps cause a slow down in growth of fruits already on the vine? I have one plant with some blueberry and grape sizes fruits going and just wondering how hopeful I can be of them growing to a "normal" size.

[carolyn137]

Originally Posted by Labradors2

Well if they are burning tires in CA to keep their strawberries from getting frost-injured! , that's another good reason for not buying/eating those awful things!

Linda

No, NO, Linda, they are NOT burning tires in CA.

If you read some of those links in the general Google link I gave you'll see that it's very specific bacteria, bacteriophages, which are bacterial viruses, and extracts of certain bacteria that have been worked with as anti-frost nucleation products.

Carolyn

Carolyn,

I don't know if they still do it, but citrus growers in Florida used to protect their citrus crops with burning soot pots placed strategically in their orchards. I always thought it was for the heat, but it may have been the soot from the burning pots that protected the crops.

When I needed a little heat while deer hunting, I carried a metal coffee can with a roll of toilet paper in it. I would saturate the toilet paper with rubbing alcohol and replace the coffee can lid. If I got really cold, I would remove the lid from the can and ignite the roll of paper. It would provide some heat for three or four hours before the alcohol was consumed. I've thought about using them under covers in my garden to ward off early spring frosts and freezes. They provide a low blue flame which is difficult to see and they don't get real hot.

Ted

[KarenO]

Originally Posted by cythaenopsis

Do the cooler temps cause a slow down in growth of fruits already on the vine? I have one plant with some blueberry and grape sizes fruits going and just wondering how hopeful I can be of them growing to a "normal" size.

Hi there, yes, cooler temps do slow things down for tomatoes. As long as it doesn't freeze though, they will keep growing so don't give up on them yet, you could have several more weeks of growing time left. Just watch the forecast for frost
KO