Possible frost....save tomatoes??

gardenerwannabe6April 30, 2011

OK, they're predicting possible frost tomorrow night and Mon. night. Will a floating row cover keep tomatoes warm enough and frost free? We planted 200, so far, so there's quite a few to cover.

Any other ideas for keeping them frost free??

Thanks a bunch!

Thank you for reporting this comment. Undo
Okiedawn OK Zone 7

Do you have floating row cover available to use? If so, I'd use it.

Whether or not it protects them depends on how heavy it is, how well it is anchored down so it can't blow off of the plants, and how many degrees of protection it is supposed to give the plants.

I have 200 square feet of heavy-duty Agribon rated to give 8 degrees of frost protection. I used it on the most tender plants. I generally refer to it as a frost blanket. It works really well.

I have 5000 square feet of a more light-weight form of Agribon that gives 2 to 4 degrees of frost protection. I use it on everything else. If I am really nervous about this material not being heavy enough, I use a double layer instead of a single layer.

If you don't have floating row covers, you can use sheets, sheer curtains, blankets, etc. If the blankets are heavy enough that they'll crush your plants, you need to put buckets, flower pots or boxes over the plants first, and then put the blankets on top of those coverings.

You can use tarps or plastic (I've used a really big boat tarp before and it worked pretty well) but any place the foliage touches the plastic, it may freeze. Hopefully, in that case, you'd only lose the tips of branches and some foliage but the plants would mostly survive.

If you don't have any sort of plastic, textile material or floating row cover, the amount of damage you might see would vary depending on how cold your temps drop and how long they stay there.

On some nights in the past, I took bales of hay, cut the baling wire so I could pull the bales apart and piled hay loosely around my plants during the early afternoon. Then, just before sunset I lightly covered the top part of the plants too, leaving an inch or two of hay on top of the foliage. (You can't put too much on top of the plants or it breaks them.) They survived with very little damage, but we only went down to 31 or so.

In 1999 we had an early first fall freeze in late Sept. (normally our first fall freeze is late Nov.). We had a small garden then and I only had to cover up two 4' x 8' beds of tomatoes, so we set up hay bales completely around those beds, literally building walls of hay bales. Them, on top of the walls, we laid sheets of 6 mm plastic. We laid 2 x 4's on top of the plastic to hold it in place. Then we threw old quilts and blankets over the plastic right around sunset to help hold any in the heat. The plants survived in that manner for 2 or 3 cold nights and went on to produce for another couple of months.

The other morning I had 37 degrees and heavy frost...heavy enough you had to scrape it off the car windshield with an ice scraper. I had not covered up my plants because the forecast low was 44. I looked at the thermometer when I woke up, saw 39 degrees, freaked out, went outside, saw frost on everything, checked thermometer again and saw 37 degrees, freaked out again, and ran to the garden with my hose in my hand to wash the frost off the plants. About 80-90% of the time if the frost has only been on the plants an hour or two and you hose it off before the sunshine hits it, you can save the plants. It worked for me last week.

Also, there is a difference between freeze damage and frost damage. I have better luck preventing frost damage than freeze damage. If actual freeze damage threatens, I try to add a heat source. In my case, I usually add buckets or milk jugs of water. I put them out beside the plants all day long so they can serve as solar collectors. I cover the plants up as described above in the hope that between covering the plants and having warmed solar collectors, I'll keep the air right around the plants warm enough to prevent freeze damage.

Some people will hang a string of Christmas lights along a row of tomatoes and cover up the tomatoes with plastic to try to hold in the small amount of heat the Christmas lights create. It may or may not work. My garden is much too far away from an electrical outlet for that to be a solution I could try.

How low do you expect the temps to drop?

The other thing I'm wondering is "What Would Jay Do?" Hopefully he'll see this thread and respond because he has cold nights well into May some years.


    Bookmark   May 1, 2011 at 12:27AM
Thank you for reporting this comment. Undo

"What would Jay do?" The answer to that question varies some. Due to the current tendencies to have the cool to cold early morning into early and mid May here I do some things before and when I transplant the early ones into the garden. And another reason I plant all of my early plants usually in post holes 6 inches deep or so. Then I put either a plastic 5 gallon bucket with the bottom cut out or a plastic coffee container around each. I put some mulch around them. Then on the predicted cold nights I put loose straw on top of them. Have had plants survive dips into the mid 20's with little or no damage. Actually survive better than in an uncovered cold frame. And another reason I don't want huge plants in early May. If they are too big they will get out of the top of the buckets or a wall o water and then the damage happens. This year I haven't put any out like I normally would due to my work schedule. But will in the next few days for sure. I use loose straw around my other plants. The problem now is my onions are big enough and with the wind I can't keep the straw around them. Ideally I would use a row cover if I had one. I have plans for the future. But doubt I will change much with my tomato plants unless I erect a tunnel sometime. And even then the growers I know around here said you really need to use the buckets ect for protection on the cool mornings. I have to use something that can be left on during the day. When you leave early like I do I can't pull it off after sunrise. Too many things will get too hot. Why loose straw works so well for me. Jay

    Bookmark   May 1, 2011 at 9:19AM
Thank you for reporting this comment. Undo
sammy zone 7 Tulsa

Our low tonight should be 38 and tomorrow night 36. My tomatoes are in large pots -- 25 in all, and they have a ring of concrete wire around them. I don't have enough sheets and blankets to cover them, and if I did, I would probably harm the plants in some way. I think I will put extra mulch around them, and try the Christmas light thing. It would be easy for me to put Christmas lights around the concrete wire, but I think our outside plug is broken. I also think my husband won't consider doing such a thing.

Everything seems overwhelming at this point. This is so discouraging.


    Bookmark   May 1, 2011 at 10:37AM
Thank you for reporting this comment. Undo
joellenh(6b Jenks)

Oh man...frost in May. You weren't kidding Dawn. I hate covering everything, but will tonight and tomorrow.

Thanks for the heads up.


    Bookmark   May 1, 2011 at 11:26AM
Thank you for reporting this comment. Undo
Okiedawn OK Zone 7


I'm glad you saw my comment and responded because gardenerwannabe is further north of me and probably has a later frost date than mine, so I was hoping your words of wisdom would be useful to gardenerwannabe.


If you set up your sprinkler this afternoon, it would be easy to turn it on for a few minutes just before sunrise (unless you leave for work earlier than that) to wash the frost, if any occurs, off the plant leaves before sunlight hits them. That generally works for me, although it isn't a guarantee of course.

Yes, it is discouraging. Keep in mind that frost damage and freeze damage are two different things. Frost damage can kill any part of the plant the frost sits upon even at temps above freezing--up to about 38 or 39 degrees. Freeze damage is more serious and can freeze plants back to the ground, or in the case of container plants, down to the soil line. However, plants that have good root systems can regrow even if they freeze down to the soil line. If good, warm, May weather falls the cold nights, some tomato plants will rebound from freeze damage in a very fast time frame. Try to keep that in mind.

I have had tomatoes and peppers freeze entirely to the ground and when that has happened, roughly 80% of them regrew and produced although my harvest began several weeks later than average that year.

I will cover what I can with floating row cover if I can. It currently is rainy and windy and I won't be able to put out row cover in the wind. So, I'm hoping it calms down before dark so I can at least cover up my tomatoes, corn and beans....I have a couple hundred bean plants that are 6 to 8" tall and I'd hate to lose them. They are more cold sensitive than tomatoes, and I think corn may be more cold sensitive as well. If the growing tip of corn plants freeze, you might as well pull up the corn and start over because it won't produce.

I don't know exactly how far south or west the risk of possible freeze or frost damage goes, but I saw a Special Weather Statement posted for a part of Texas as far west as Abilene and as far south as San Angelo (!) that warns them of the need to provide protection for tender vegetation and livestock on the next couple of nights. So, if y'all think we are frustrated (and we are!), imagine the folks in San Angelo, where the average last freeze date is usually the last week of March.

I hope we stay above freezing tonight when the forecast is 44 (which last week gave us an actual low of 37). Frost needs for all the conditions to be "just right" in order for it to occur. Some conditions that contribute to it are a lack of wind overnight and clear skies, which allow air to cool a bit more than expected sometimes. So, depending on anyone's specific local conditions, you might or might not get frost in the 30s. It is a really iffy deal. I just know that at our house, late frost is a very common issue May 1- May 4 of most years, and it looks like it is happening again.

Tim's teaching the first 3-hour segment of a 30-hour Basic Firefighter training course this afternoon and we won't be home from that until 5 or 6 p.m. which won't leave me much daylight to cover up anything at all. I can't cover it up before we leave because of the windy, stormy conditions occurring right now. I'm more worried about tomorrow night than tonight, but tomorrow night won't matter much if we frost or freeze tonight.

My tomato plants are too tall and too wide for buckets, so that option is off the table for me anyway. I may be outside tonight putting out row covers with a flashlight at 8 p.m.

It is cold and chilly here today. Our temp is in the low 50s and the wind chill is 43. A big storm is rolling in right now with very dark clouds and thunder from our southwest. Looks like we're having spring today and winter tonight. Only in Oklahoma is there the possibility you'll have all 4 seasons in the same week, or even the same day! Sometimes I think we just have to laugh about our wacky weather or it would make us cry.


    Bookmark   May 1, 2011 at 11:30AM
Thank you for reporting this comment. Undo
sammy zone 7 Tulsa

I am so naive about tomatoes, but what is the difference between hose water and frost? I have the hose near the pots, and can easily wash them, but isn't one water about the same as another?


    Bookmark   May 1, 2011 at 11:55AM
Thank you for reporting this comment. Undo

Dawn glad you mentioned the difference between frost and freeze damage and how a plant can recover. I'm sure you saw me mention 2 weeks ago I had a large plant that the top was touching the glass on my cold frame. We had a few warm days and nights in a row and I hadn't realized how much it had grown. As I was moving the big plants to another area hardening them off during the day and moving them back around night fall. A night where the low was supposed to be 34-36 and instead dropped to 26 briefly before rebounding. It froze the top that was touching the glass. That was all. Now 2 weeks later hard to tell there was much damage. They do rebound quickly. But a friendly reminder is if covering it is ok for straw and even a blanket to touch the plant. But anything glass, plastic or metal can cause damage if touching the plant. A lot of the new covers I see are ok. I have used the plastic coverings before and learned the hard way when the wind blew it down on some plants one night. So when covering plants it is best to be careful what you cover with and how. Jay

    Bookmark   May 1, 2011 at 12:42PM
Thank you for reporting this comment. Undo

Thank you all for the helpful tips.....I think I'll try the floating row cover. I don't have enough to cover all, so I'll probably use sheets on the rest.

Also, these plants were just put in the ground yesterday, so that has me even more concerned. Will that be a huge factor in determining their future rebound??

Thank you all so much...your knowledge is always so helpful!

    Bookmark   May 1, 2011 at 1:04PM
Thank you for reporting this comment. Undo

Wow. You guys/gals are some hard core gardeners. I gotta hang around here and learn learn learn! I'm so glad I did not plant my 6 little 'mater plants yesterday. I'm going to just sit them in the garage tonight. Yikes. Frost in May. My. Mom said she would never plant a garden before May 15th in OK because it was too unpredictable.

    Bookmark   May 1, 2011 at 1:22PM
Thank you for reporting this comment. Undo
Okiedawn OK Zone 7

Sammy, Frost can form at 37 or 38 degrees (many people think you only get frost at 32 or lower) and even 39 degrees under certain conditions. It damages the plants, though not necessarily as much as freeze damages them.

See the linked page for into on how or why hosing the frost off the plants appears to help prevent damage. Ir is in either the last paragraph or the second-to-the-last paragraph. There is some disagreement about whether or not hosing off plants really works, but my feeling is that in my experience it does, but only if I hose off the frost before sunlight hits the plants.


I learned the hard way after moving here that my "average last frost date" of March 27-28 is completely useless, but it took losing plants repeatedly for me to start paying more attention and covering up plants more consistently. Usually I blame the late cold on our particularly low-lying microclimate near the river but this week's cold looks like a really widespread event.


You're welcome.

It just depends on how well hardened-off your plants were and how large their root system is. If your plants have been outside on some pretty chilly but above-freezing nights, they ought to be OK as long as they are covered. If they haven't been exposed to many cool nights, I'd be a bit more worried.

Whatever happens, if they look dead tomorrow or Tuesday morning, don't panic and pull them up. Often you'll see new growth from the ground in about a week. I'my also NOT going to suggest you run outside and dig up all 200 of them because (a) that would be too much work and (b) I don't want for you to throw an imaginary trowel at me.

If you haven't had rain, check the soil in their root zone and make sure it is moist (I assume you watered them in after planting them yesterday) because dry roots are damaged more easily the moist roots.

You must have my kind of luck. No matter how often I check the forecast and how carefully I select a planting date that seems weather-proof, just as soon as I'm done, a new forecast comes out with (choose as many as you wish): sleet, snow, hail, freezing rain, severe T-storms with 70 mph winds, wildfire, or flooding. It is frustrating and there are days I come "this close" to just having a big hissy fit over the weather, not that throwing a tantrum will change it or anything.

By the way, seeing your post last night made me smile. I was happy to see you here. You hadn't posted in a while and I wondered if you were still gardening.

Just do your best to cover up what you can and then hope for the best. The weather is one of those things we cannot control and we just have to deal with it.

I have done some very creative covering-up of plants back in our earlier days here before I had accumulated a large supply of buckets, blankets, floating row covers and bales of hay. During one especially memorable cold spell I used every bucket we had on the property including my mop bucket, large soup-type stock pots (I had 4 huge ones, so that was 4 plants saved), mixing bowls, old curtains, table cloths, quilts, bed spreads, sleeping bags, bushel baskets, wicker baskets (hay was piled on top of all the baskets), tents, cardboard boxes (with hay and leaves on top), tarps, large drinking glasses, 2-liter soda bottles with their upper portion cut off and discarded, black trash bags placed over each cage (too thin to help much I think), etc. Once, when hail threatened around 6 p.m. and I had just that day put about 50 plants in the ground on a lovely sunny, clear afternoon, I carried my 5 white folding plastic tables to the garden and lined them up over the bed of tomatoes. When that left plants uncovered, I carried out lawn chairs out and used them to cover up more plants. I hung quilts over the tables and chairs. We had a pretty intense hail storm, but all my plants survived. My garden looked ridiculously like I was planning a garden dinner party right in the garden, but my plants lived.

Erod, I like your Mom's thinking and agree with it in principle, except that we can get too hot too early for it to work for me. The issue with deliberately planting late is that it makes the harvest late, which can be a big problem with tomatoes. Often, the heat reaches levels in mid-June that interfere with the proper fertilization of tomatoes, so we need to plant as early as we can in order to get a good harvest and an early one.

I expect to harvest ripe tomatoes from in-ground plants before Memorial Day every year as long as I plant in late March or early April and cover up my plants on late cold nights. If I waited until May to transplant tomatoes into the ground, I wouldn't have nearly as early or as large of a harvest as I normally do.

The "old-timers" here in my county often wait until April 1st to plant, but in recent years even that is too early to avoid frost or freeze damage. I have planted as early as March 7th or 8th and not lost a single plant, but that was during the late 1990s and early 2000s when we kept having hotter-than-average winters and springs.

It seems to me, at least in my part of OK, that we are having wilder weather swings from hot to cold and back again in spring and that there's been a very definite weather pattern change for us beginning around 2006.

My poor cool-season plants had temps in the 80s and 90s in March and April, and now my warm-season plants are facing temps in the 30s and low 40s. I feel like I am Alice-in-Wonderland and have found myself in some strange new world I don't understand.


Here is a link that might be useful: Washing Frost Off Plants

    Bookmark   May 1, 2011 at 3:06PM
Thank you for reporting this comment. Undo

A few years ago I had planted eggplants too early. They had grown a bit, and then a freeze was forecast. What I did to protect them might be useful for some of you.

I garden in on a ridge which was forest before I began clearing. I tied a rope from a tree over to a stump, with the rope being over the row of eggplants. I then laid plastic sheeting over the rope in tent style, throwing dirt on the edges of the plastic to hold it down. Under the "tent" I placed jugs of hot water, just before going to bed for the night. I made sure the plastic did not touch the eggplants. They came through the freezing weather just fine, and we had a good crop that year. I believe that was the first year I ever grew eggplants.

Now, to adapt that to your circumstances. Take t-posts or some other type of sturdy post and drive them in at the end of each row. Tie a rope between them, and make a tent over that rope. Put jugs of hot water in late at night or a couple of hours before daylight when the frost is most likely to occur. If your rows are too long, add additional post in the middle. Sheets may work as well as plastic sheeting, at least for frost danger.

Alas, I myself have too big a garden to do as I have just described. My rows are fairly long, and there are a lot of them. But, I live in southern Oklahoma, and on a ridge. The temps may not get as low here, and being on a ridge helps in that the cool air sinks and goes down into the valley and thus often spares the garden. I'm going to see what tonight's temps get down to, and then decide whether I need to attempt some saving measures tomorrow night. For where I am, I believe tomorrow night will be the potentially dangerous time. Being on a ridge with steep hills on both sides has been the saving grace more than once here.

While t-posts are not cheap, all of these things, (posts, rope, heavy plastic) are things which can be stored and re-used year after year. If you have a small enough garden, and are willing to go to the effort, it might make a difference.

Good luck everyone.


    Bookmark   May 1, 2011 at 4:59PM
Thank you for reporting this comment. Undo

okiedawn, thank you for the link about washing frost off plants. I just read it after making the post up above. Very interesting, and I believe it works.

Think about how you make homemade ice cream. You add ice, and then to cause it to melt you add rock salt. It is the melting of the ice which draws the heat from the ice cream mixture, dropping the temperature and eventually causing it to begin to freeze. It is the same principle at work when frost melts on plants and causes damage.

When you wash the frost off the plants, instead of heat being drawn from the plant, and thus causing damage to the plant tissue, it is drawn from the water you are spraying. Once the frost is washed off, it no longer poses a danger.

This is the first time I have heard of washing the frost off plants. Thank you for the very handy tip. I hope to not have to utilize this new information, but it is encouraging to know that I have another tool to use to prevent the damage.


    Bookmark   May 1, 2011 at 5:47PM
Thank you for reporting this comment. Undo
Okiedawn OK Zone 7

Okieman, While you're up on that ridge, I'm down here in the valley!

Believe me, were it not for the pouring rain, wind and lightning I'd be out covering up everything right now.I have all the Agri-bon to do it, but we have wind and lightning along with the rain that's falling. As it is, nothing will be covered, but I brought in everything still in flats, which is only my pepper plants and some back-up tomato plants that I kept just for this reason. At least if my in-ground plants freeze, I have replacement plants for about 1/3 of them.

We are supposed to go down to 44 degrees tonight here south of Marietta, but our temp has been fluctuating between 45 and 46 for the last hour or two, so I don't really think that we'll only go to 44.

My potatoes, onions and sugar snap peas are big gigantic monsters but of course, I don't think it will get cold enough to harm them irreparably tonight. The tomatoes, corn and green beans are a different story. Guess I'll just have to cross all my fingers and toes and hope for the best.

If the weather cooperates, maybe I can cover up stuff tomorow.

I assume you have rain there as well.

Really, with the early hot weather, late cold weather, lack of rain, then too much rain, hail, wind, etc., I'm just relieved to still have any garden at all at this point.

The frost thing is interesting. I always wash the frost off even if I think it "may not" help. I just always figured it "couldn't hurt". I like the analogy you made to making homemade ice cream, except it made me want to pull some of last year's peach crop out of the freezer and make some home-made ice-cream right now. : )

The NWS is warning of possible frost/freeze issues as far south as San Angelo. Now, I think THAT is crazy for May.


    Bookmark   May 1, 2011 at 7:38PM
Thank you for reporting this comment. Undo
joellenh(6b Jenks)

I want peach ice cream.

Dang you all for making my fat butt hungry.

It is 43 here right now, so I suspect frost is in the nightly forecast.

On top of having to pull 10+ blankets out of my closet every time this happens, I am SO SICK of the temp roller coaster.

Two days ago I had the AC on and now I had to turn the heat on (49 in the house and I am COLD)
This weather is CRAZY and if I have a chance to move somewhere more temperate I am going to take it.

Much as I really love and adore OK the weather is just THE PITS


    Bookmark   May 1, 2011 at 8:30PM
Thank you for reporting this comment. Undo
Okiedawn OK Zone 7


I want some peach ice cream too but I'm too cold to make it tonight.

I'm thinking maybe tomorrow I'll make some because now that I have the idea of homemade peach ice cream in my head, I really want some. :)

This weather is THE PITS, I agree, and too rainy and windy here to cover up anything tonight. If my plants surive tonight, I'll cover up stuff tomorrow.

Don't you dare move somewhere else more temperate! If we have to suffer here, you have to suffer here too. Besides that, this forum wouldn't be the same without you.


    Bookmark   May 1, 2011 at 8:51PM
Thank you for reporting this comment. Undo
joellenh(6b Jenks)

Aww Dawn you just made me tear up.

So I am coming down there tomorrow to eat some ice cream with you. :)


    Bookmark   May 1, 2011 at 9:18PM
Thank you for reporting this comment. Undo


Yes, we've had a good amount of rain today, but it is starting to clear up and get still this evening. The weather has been crazy for sure. I believe that on the short term it has been due to the La Nina weather pattern. But, I also think we have climate change occurring too. Maybe caused by man, maybe not. Regardless, it does appear to be changing. Also, I've read that some of the volcanoes on the Kamchatka Peninsula in Russia have influenced conditions in the Arctic Region of North America over the past year. Volcanic dust in the high atmosphere influencing wind currents. I don't know for sure whether this has had much of an influence or not though. I personally believe that as we have more global warming this causes more robust movement of the jet stream and other air currents around the world. The result being extremes occurring when they dip into the lower latitudes (or rise into higher latitudes) than in the past. Warmer warm spells and colder cold spells.

Good thing I did not mention cheese cake or coconut meringue pie in my discussion about washing off frost. Oops, I guess I just did. Let's add in a German Chocolate Cake with dark chocolate FROSTING and we will round things out. If we're going to have frost, let's make it chocolate. Dessert for everybody!

    Bookmark   May 1, 2011 at 9:39PM
Thank you for reporting this comment. Undo
joellenh(6b Jenks)

I now need chocolate, cheesecake, and peach ice cream.

Party in jenks?



    Bookmark   May 1, 2011 at 9:50PM
Thank you for reporting this comment. Undo
Okiedawn OK Zone 7

Jo, Come on down. It would be a long drive just for some ice cream though, wouldn't it?

Okieman, Oh wow, are you trying to make us hungry or something? Clearly we all use food as our "stress reliever" because here we are all stressed out by the prospect of very cold nighttime lows and all we're thinking about is rich, fattening sweet foods.

I agree with you that some sort of global warming, manmade or otherwise, is occurring and is giving us more extreme weather. Look at the record number of tornadoes for the month of April 2011. I wonder if May will continue on in the same manner.

And, believe me y'all, as much as I'd hate it if my garden freezes tonight or tomorrow night, I know how incredibly fortunate each and every one of us is right now compared to all those across the south who have suffered from tremendous loss and pain in the recent rounds of tornadic weather. When I think of what they've been through in Tushka, OK, and across Arkansas, Missouri, Alabama, Georgia, Tennessee, etc., I know I have nothing to complain about it. I know we're all lucky to have gardens to worry about and fuss over and my heart goes out to all those who've lost their homes, belongings, loved ones, friends, neighbors, etc. Thinking of them should help all of us take our garden "problems" with a grain of salt.

Right now it has warmed up to 47 degrees at our house! Woo hoo! That's about as warm as it has been all day. Our rain seems to have ended at least for a while, but a few minutes ago I was still seeing lightning in the skies east of Marietta.


    Bookmark   May 1, 2011 at 10:38PM
Thank you for reporting this comment. Undo

Whoever named "floating row cover" - "floating" row cover, obviously did not live in OK. "Flying row cover" would be much more appropriate! LOL Our neighbors already think we're crazy for having a large garden. Now they know we are after watching us wrestle those covers in the wind to protect our tomatoes. Oh well......Now we just watch and wait :)
It looks like Mon. PM may turn out to be the more severe chance for frost...but this is Oklahoma, so who really knows???


    Bookmark   May 1, 2011 at 10:43PM
Sign Up to comment
More Discussions
Purchased comppost and soil.
Somewhere recently I read a post that had a phone number...
AmyinOwasso/zone 6b
Ark. traveler tomato
Some one sent me a few seeds last yr. and I didn't...
2015 Spring Fling Anyone?
It must be so. I've reserved a porta-potty and marked...
Cover crops that help with root rot
I just listened to a soil health talk on the web. My...
People viewed this after searching for:
© 2015 Houzz Inc. Houzz® The new way to design your home™