11: Episode 11 – protecting seedlings from frost

Managing frost can be tricky at the start of the season. The longer you extend your planting season, the more you expose your plants to frost and the risk it presents. Even with the most risk averse attentions a late frost can catch you by surprise and decimate your crop before its even got a foothold. Here I talk about some cheap and free ways to protect your young plants from frost.

Send in a voice message: https://anchor.fm/self-sufficient-hub/message


Protecting Seedlings From Frost

We're going to be talking about how you can protect your seedlings from frost. Everywhere has
a different last frost a day. You can find this online and this is the date that traditionally would be
the latest you could expect a frost. So the actual day of your last frost any given year is likely to
be earlier than your last frost date. That is the last date you could reasonably expect to get a
frost. From this day onwards, it's safe to assume you won't.
What that means is that on or around that date, you're ready to let your garden go on the
assumption that you're not going to have any frost. It still makes sense to keep half an eye on
the weather because the climate is changing all the time, but on the run-up to the last frost date,
the chances of you having a frost get lower and lower. So it's very tempting to get your plants
out a little bit before this date and when I say tempting for me personally, it's irresistible and I
don't even try to hold off for that date any longer, I simply go for it.
The downside of this is that you are exposing your seedlings to the risk of frost for a lot longer
and at a lot higher frequency. I've already planted out a fair number of seedlings that will need
to be protected from the frost because the frost will kill them. I'm going to go through a number
of different ways of protecting our plants from that frost and tell you how you can do the same.

How To Protect Your Seedlings From Frost

Greenhouse or Polytunnel

The first thing is a greenhouse or a polytunnel. If you’re growing your seedlings in pots or trays in a greenhouse or a polytunnel, then chances are they’re already protected from frost. That’s the first thing you need to remember because that’s doing the job. If you’ve got plants out in pots, even if you’re growing their seedlings in pots, you can always just bring them inside of the polytunnel or the greenhouse to protect them.

But if you’ve got them growing in the ground as I do, then you’re going to need to do one of a number of other things to protect them from the frost. You need to be aware of how deep that frost is going to be because if it’s only a light frost you only need to take very light measures but if it’s going to be a deep hard frost then you need to think a little bit more.

Hoop House

One of the favourite methods I have is a hooped run. It’s about six little wire hoops with clear plastic that runs over the top of them and I bought these from the one-pound shop two years ago and they’re doing really well. They’re still holding up fine. The reason I like using these is the cost. They’re just so cheap. For 10 pounds, you can get enough to cover a significant number of rows of plants. You set these up by pushing the edges of your loops in the ground either side of your row and then a piece of string at each end just pulls them tight.

The upside of these is that they’re semi-permanent so I can put them in when I plant and I cannot worry and it’s almost like those seedlings are growing in a greenhouse until I take them away. The downside can be if we’ve got really unseasonably hot weather and bright sunshine, then some of the plants that you might have growing under them can perhaps scorcher little because they’re quite delicate and so small. But that’s really an outlier for that to ever be an issue.
If you don’t have anything like that and you have to make do with what you have around you, then I’ve got three other methods that are super simple and I’d be stunned if you didn’t have at least one of these available to you.

Jam Jar

The first one is a jam jar or something similar. You take the lid off, turn it upside down and place one on top of each of your seedlings. Now if you’re mulched like I am, this can actually serve two purposes. If you’ve got tiny, little seedlings, then this is going to enable you to mark your rows a little bit easier because you’re going to be able to see where everything is in your mulch. They are working exactly the same as a greenhouse. So it’s not a bad idea. Even if you’re not going to get a frost, they’re going to help give your plants that extra boost.
One thing I do want you to be aware of though is that they’re going to recreate that greenhouse environment. So you’re going to have to go through the process of hardening off again if you’ve got nice warm weather and you’re leaving them in place. When you come to remove them, just do it gradually. First of all, just remove them during the day and then slowly remove them overnight when your plants get strong enough and you feel that they’re ready to be hardened off that way.

Plastic Bottles

The next one is plastic bottles. I like to use these for things like peas. I cut both ends off the plastic bottles like an orange squash bottle and I like to feed that down over the cane that I’m using for my peas to grow up. I do this regardless of the weather because it also serves a fantastic second purpose when you plant peas and beans. Quite often they’re going to be seen as food by some of your friendly garden pests and I’m talking about mice, pigeons or anything like that. They’re going to love to find a pee while they’re scratching around on your soil. These semi clashes if you like without a lid serve two purposes.

They protect the plant from frost that’s growing but also they protect it from the pests that want to dig it up and eat it for their tea. One thing you do need to be aware of is that if you’re going to get a super hard frost, you might want to place something over the top as well like some plastic or cling film because the bottles that I use, I’ve cut both ends off because I leave them in place once they’re in and the plant grows up out of them and up the cane. If you’re going to use that method, just be mindful that the top is open and therefore if you get a really hard frost then the element that’s inside that bottle is still going to be susceptible.

Straws and Grass Clippings

The last way of protecting your seedlings from frost is by using something like straws. Straw is a great insulator because you can kind of fluff it up a little bit and it creates loads and loads of lovely air pockets. It’s also super light so it’s not going to do too much damage to your seedlings by pushing them down.

I’ve used grass clippings as well but I tend to use that more when I actually plant when I’m trying to protect a seedling. I’m certainly going to use hay much more common than grass clippings because grass clippings are going to weigh down on the seedling and probably damage it whereas, with hay, you can fluff up and really protect it. I tend to use hay quite a lot on my potatoes as well for their first covering because it gives them the opportunity to carry on and grow up through it really quickly while at the same time keeping the sun off those first few.

Final Thoughts

These are all the ways I use to protect my seedlings from the frost. Keep an eye on the weather and be proactive. Take those steps because there’s nothing more disheartening than coming out and just seeing a lovely row of vegetables that were just coming on or wilting because they’ve been frostbitten. Take all precautionary measures. You’ll appreciate it and it will certainly pay you back.