As a gardener there are a lot of things that you can do to protect your flowering shrubs and fruit bearing trees and shrubs from frost damage in the early spring. Of course the size of the plants determines how much you can do and be successful.
Frost is the quiet enemy that looks in the night.
But it’s important to distinguish between a hard freeze and a frost. When it drops down to 32 degrees F. and stays at or below that temperature for an hour or more freeze damage is likely to occur. But a frost can occur even when the air temperature is above 32 degrees. A frost will damage some plants, others it will not. Those most at risk are fruit bearing crops like strawberries, peaches, grapes, apples and so on. A frost usually doesn’t do long term damage to the plant itself, but it can and will kill the blooms before they can be pollinated and before fruit production can begin.
Looking for a few people who would like to get paid for growing small plants at home.
Create a breeze to keep the frost aloft.
Farmers who grow fruit crops for a living must take an aggressive approach to controlling frost damage if and when they can. In the grape vineyards here in Ohio they figured out that if you can keep the air moving over the vineyards that often enough to keep frost from settling in. So many of the grape growers have stands built at the end of the vineyard that support airplane engines propeller and all. On nights when frost is predicted they start up the airplane engines and run them at fairly high speed to create artificial air flow over the vineyards.
Add water, create ice, add more water!
Strawberry growers, apple growers and I’m sure other warmers actually water their fruit crops early in the morning before the sun comes up in a effort to wash off the frost before the sun hits it. Apparently the frost on the bloom isn’t near as damaging as the sun hitting a bloom that is covered with frost. I’m not sure what the scientific reason is, but I do know that it works. They start watering before the sun comes up and often times the water freezes on the plants creating ice formations. The farmers just continue to apply more water over the ice until it warms to the point that the ice melts. As long as they keep apply water until the temperatures rise, all is well. Sounds crazy I know, but it works.
A few at home strategies that work.
So at home with a small number of fruit crops what can you do to save them from a coming frost? It’s probably not feasible for you to create a breeze in your yard without having the neighbors trying to have you committed. But you can use your garden hose to wash the frost away. Get up early before the sun comes up, or just as the sun is coming up and try rinsing the frost from your plants.
Be Careful, don’t blow up your plumbing!
What???? Keep in mind, come winter you should disconnect all garden hoses from the sill-cocks so the water can drain from the fixtures so they don’t freeze and break. Today most of our homes have frost freeze sill-cocks to protect them from freezing. However , these fixtures are only frost free if you disconnect the garden hose so the water inside the fixture can drain out. If you leave the hose connected the fixture will freeze, break and could create a real mess in, or under your house. So if you’re out there in the early spring hooking up a garden hose, be sure to disconnect it as soon as you are done.
Use the heat that Mother Nature has provided for you.
Ground heat baby! Ground heat! In the nursery business we take every opportunity possible to utilize the natural heat from the ground. As you probably know the earth is warm. Things below ground rarely freeze. They never freeze if you go below the frost line. So with plants that are close to the ground you can protect them from a frost, or even a freeze if you cover them up. You can use plastic, newspaper, bed sheets, plastic tarps, anything you can find. But the thicker, more insulated the covering you use, the more protection you are providing for your plants.
Around here we have a store called Harbor Freight and they also have a website where you can order online. But they often advertised padded movers blankets at crazy low prices. Those things would be perfect for covering strawberry plants, maybe blueberries or other low plants that you would like to protect. A heavy covering like that would do a great job of trapping in that ground heat. Many gardening stores sell frost blanks and other devices that you can use to cover some of your fruit and vegetable crops from frost.
There you have it, I hope you found this useful. Questions or comments? Post them below.
Looking for a few people who would like to get paid for growing small plants at home.
Hello Mike.,
I have a 3X5 bed against the house where my bird of paradise and boulglava grows. I have drove in 8′ stakes and made an enclosure from plastic around my plants with the house as the 4th side.. Do I need a top on my enclosure? It reaches four feet above the plants and the overhang from the house offers some protection but there is still a 2 foot opening. We frequently drop below freezing at night with days running in the high 40s to mid 50s.
Theresa,
It’s important to understand that if you live in a cold climate there is little that you can do that would be considered practical to keep outdoor plants from freezing. All plastic coverings offer protection, but they don’t prevent freezing. And as long as you are growing plants that are hardy in your climate, they shouldn’t need that kind of protection. Hardy plants actually need to freeze. It triggers them into dormancy so they can rest for the winter. So as long as your plants can take the cold weather the protection that you have provided should be sufficient.
Hi Mike , I love your tips and idea, but trying to get my husband to help is a problem. He thinks he is the “Gardener” Lol
Hi Mike,
Quick question, what do you think about the Master Gardner course offered through MSU.
Thanks
Marsha
Edit my previous comment. What I mean about heavy plastic is that I use it elsewhere. Over late zucchini for instance. The growing tips are hidden down near the ground.
Hi Folks
I’m in zone 4b but sit low in a valley so get lots of frost. The cardboard boxes from fridges and larger items can be cut down two diagonal sides and used like row covers. tape up the ends and cut across or cur out ends and tape or staple on. Last fall I had these 4 foot wide flat pieces that I made a fence with around a small tomato patch (5×8 feet). That box was covered with a white tarp suspended on the tomato stakes. I left one end so I could open it and left that on all week due to very low temperatures. I believe it was the ground heat that allowed me to get most of the late cherry tomatos. I used heavy plastic but need two layers slightly crumpled up so tyhere is some space betwwen them. Thanks Mike and everyone for all the good tips.
Bruce
I have always made tents with stakes, wire and whatever cover I can come up with. Cardboard is good, the larger it is the better it works for a tent. I water early and before daylight if I get caught in an unexpected frost to save the tomatoes. Duct taping cardboard together makes nice big sheets to work with and folds up out of the way.
“Frost is the quiet enemy that looks in the night.”
Is the word you really meant to type “LURKS” maybe?
Joanna,
I meant lurks, what I actually typed is anybody’s guess. Of course I was working from a hotel computer at 6:00 in New Orleans. I could have typed just about anything.
I just took my big beach umbrella and only open the top half and put over my peppers that have stakes around them because frost falls from above right?
Dorothea,
That should work.
How to protect the Potatoes from the frost ? Is smoke a solution ?
My Grandpa always did 2 things to combat late Spring frosts and for freezes. He made a tent over many plants, using plastic and very slim poles that were taller than the plants. I remember he had everything available to make ‘tents’ for the plants.
The second thing he used was for shorter plants. Boxes! He had a collection of card-board boxes, that he kept in the shed, just for ‘freezes.’ We have done the same with the boxes, and didn’t even have to remove them at daylight.
I only wish I would have been old enough to learn how he always planted from seed. Our last frost in the FAR (real) Northern California mountains is normally around June 10th. I have had to cut back on plants, since I can no longer work, due to MS. They are just too expensive! So we don’t have as much of a garden or flowers as I used to have. How I miss that! Anyone who gets to plant from seed is SO Blessed!
Lin
(Just below the Oregon border)
Hi… I purchased 10×12 frost blankets for $7.29 a piece. Living in central Mississippi, we don’t have too many nights that dip below 32º, but these blankets work for me at a cheap price. They are sold by Grow More on Amazon.
I set up sprinklers (on top of 8 ft posts, with timers on the feed hoses) and let them mist the garden every hour(for 10 minutes) from about 2 am till after sun’s up (depending on expected & duration of low temps). I do this in the Fall as well — last year got almost a whole extra month of tomatoes when everyone else’s were long since frozen!
hello from w ,v, thanks always injoy your emails. we always have a frost mid may. after the blooms come out, so i cover up with what i can find handy. and spray water before the sun come up on my trees. thanks
P.S. my education has been that (news)paper and/or cardboard have always been the cover of choice NEVER plastic (as Richard pointed out). .
Thanks Mike for the information. I planted two dwarf peach trees and a dwarf cherry tree last fall and I was wondering if I should worry about the drastic changes of weather here in NY. I know what to do now! 🙂
contd. raise the temperature enough to keep the plant from freezing. The water within the plant contains enough other substances to make the true freezing below 32 degrees–for some plants 31 or 30 degrees. Spraying water on the plant keeps the temperature at 32 and in direct contact with the plant thus prohibiting the plant from reaching it’s true freezing point. Freezing water emits heat and will maintain the 32 degree temperature.
I know that a chemist should not try to explain physics but I think that I can provide some help about the freezing issue. Different surfaces have different impassivity properties. This is why ice can form on a windshield when the air temperature is 34 or 35 degrees. The glass surface being reasonably good at infared emission will be 32 or below. When there is not much air movement the air temperature may be 34 or 35 but the plant’s leaf temperature can be 32 or below especially if the sky is clear. Using a fan may allow the warmer air to raise the leaf surface temperature of the leaf enough to
I’m sorry but one more thing if you use old blankets or burlap you can use clothes pins to hold and wrap your plant up just clip the cloths pin to the branches of your plant 🙂
that’s a great idea about the clothes pins.!
Hi Mike,
I live in Florida and we do tend to get frost every now and then but what I do is wrap strings of Christmas lights around my hard stem plants and with the extra lights left I tuck them down by the root ball of the plant. Works great every time.
Me, too. I don’t have trees but when my patio plants needed protection from freezing rain (which does actually happen, here, in California) i, too, hauled out old (not LED) strings of christmas tree lights & rigged up some PVP pipes & clear plastic to create a tent with the little lights strung along the pipe. It works just fine. Recently, i bought a small greenhouse made of plastic pipe & vinyl and expensive exotic (baby) plants. Because my 3rd-floor balcony apartment is on the Monterey Bay, it gets VERY cold out there & the plants need a bit of warmth nearly all the time. I “borrowed” one of my kitty’s 3 heating pads and laid it on the bottom shelf of the small greenhouse and it works great. While i’m not totally surprised that it works, i AM very, very pleased. The cat’s not that happy about losing one of her warm, comfy spots so i’m off to the store….
Mike
I too would recomend something to raise the sheets up off the plant, a wet blanket will freeze through just like plastic. Last year we lost over thirty flats of our first tomatoe crop one night under a heavy frost blanket that was just laid out on top, we had enough rain to wet the blankets then a hard freeze and every plant that was touching the blanket had a brown top plus that is where the first flowers are………
Darold
Thanks for the info. I have something else to talk about. I just retired and would like to grow my on plants from seeds. I live in Lake Charles La in zone 9. I listen to your comments about not needing a green house and I probably could use plastic pots. Could you make comments about this in your next e-mail letter. I don’t mind buying your book but would this address growing from seeds in different zones.
Thanks,
Just Retired
water well, early during the day before the frost evening
don’t ever do it late or at night ;it’ll be worst than doing nothing/that works for veggies,for trees-try one and let mike tell us the results
thanks for tryng
Mike, this reminds me of Farmer Boy by Laura Ingalls Wilder. They did that to save a corn crop (I believe)
Thanks for all informations I got from this site. Dear Mike if you are writing the book I am going to buy it, I have this credit card now. Thaks
Mike,
Great article about frost protection but a caution on the use of any kind of plastic sheeting that is in direct contact with plant foliage. The plastic actually transfers the cold to the leaves and may cause greater harm than no covering at all. Cloth is the answer and even if it doesn’t reach the ground, just the rising heat from the soil beneath will help. Just watch as the winter snow melts first under your yard trees. Low growing plants are much easier than trees and the frost cloth is a great option because you can leave it on for a couple of days if you need to. Just open the bottom during the day so the bees can still get to work. Thanks again, Richard
I AGREE with Richard. I was gone to my Dad’s funeral & ask my B-I-L to cover my things. HE USED Plastic — needless to say, that caused some damage & I lost them. I used sheets & light blankets & it works great.
I am in Tucson, AZ, and would strongly suggest NOT using plastic to cover plants unless it cannot come into direct contact with the plant itself. I have seen what happens to the leaves that touch the plastic – they freeze! Try cotton products at least for the first layer. You will get better results!
Put them over the plants. If you are worried about crushing the plants put out some thing to help hold up your cover a bit. Milk jugs, or pop bottles filled with water work well. But unless its a very heavy blanket don’t worry about it. Here in Colorado at 7,600ft we do this kind of thing at both ends of the growing season.
Frost protection- using ground heat,In the example where you say plastic, I have found that if you use a very thin plastic (as in thinner than a yard garbage bag)where ever the plastic touches the plants the coldness transfers through and damages the plants.
re: ground heat–in covering the plants, are you saying use the blankets, plastic, etc., as ground cover or to put OVER the plants?
Hi Elizabeth,you can use the blanket’s safely,but if you use plastic,make sure you take the plastic off after the temp risees,otherwise the plastic will burn the plant’s.Not the plastic itself,but it can magnify the heat,& light. Covering them keep’s the dew off the plant that would freeze,thus damaging the plant’s.As soon as I get up the next morning,I take the coverings off,& use them again at the next chance of frost.Happy Growing!
Hi, I’ve moved To Florida from the Pacific Northwest so I don’t have to worry about frost/freezing very often.
But, I have learned to use cotton sheets. I pick them up at garage sales for next to nothing.
The only problem is that a neighbor down the street has NUMEROUS cats in her home and feeds feral cats from her patio.
The cats discovered that the sheets over my large begonia bed looked pretty inviting for a place to roost for the night!! Needless to say, they broke off every begonia in the bed even though I had several stakes up to keep the sheet from crushing the begonia’s.
Any help to discourage the cats is very welcomed. I have 2 cats myself and they know to stay out of the beds, but our sandy soil in Florida is heaven to the feral’s, everything to them is fair game for their cat box!!! HELP!!!
Deb,
Thanks for the great idea about bed sheets. Your problem prompted me to do an article about predator pee to keep animals away. I’ll get to work on that today!
I suggest hanging up old cds or dvds on stakes. It will work in the daytime for keeping birds at bay. I have not tried it at night so I really cannot say if it will.
Good luck.
Hi Mike.
Have enjoyed your emails for some time now.
I’m not sure, but you may want to change the wording in your headline. Perhaps it should say: “Frost is the enemy that ‘LURKS’ in the night.
Hope this helps.
A.J.
Hello Mike,
Hello Mike,
I always learn so much from your newsletters. It seems out here in the N.W. we are going to have a early Spring, but it still drops in the low to mid 30’s at night. I was wondering if a couple of small old fashioned oscillating fans would do the trick on a small area. Also another question. Is it true that plants under the cover of a porch roof will not be harmed if the frost cannot fall on them, in the 3o’s during the Winter?
Thank you,
Sylvia Griffin