I decided to make two lids instead of a large one for my frame. I used four shorter planks and two longer ones.

These brackets will help keep the structure stable, and it makes the lid more durable too.

It's time for some Garden DIY, building a cold frame lid! This lid is very easy to make and it give your vegetables a chance to survive just a bit longer, even when the season is ending. This is how it's done.

I started by screwing wooden boards together, with battens in the middle. My frame has two long and four short sides. I also added brackets in the corners to make the structure more stable, this is especially important for large and heavy lids.

Use a staple gun to mount greenhouse plastic on top of the wooden structure. Make sure that the plastic is completely stretched. The frame I'm building the lid for is slanted so water doesn't gather on top, but snow sometimes does. That's why it's good to have a few extra battens in the middle to help carry the weight.

I folded the plastic over the lid and used the staple gun to fasten the plastic on the inside of the lid too. This will prevent the plastic from breaking if it gets weighed down by snow.

Condensation has affected the wood on this frame. This will most likely happen, but it's not that big of a deal. I built these lids in 2013-2014 and they have been outside ever since. I think I can keep using them for many years to come.

I'm growing spinach, pak choi,  arugula and lamb's lettuce in this frame. I sowed the seeds in August.

Watch: Lambs lettuce – hardy leaves for winter gardens

Insulating your cold frame lid

Some people build lids that you can attach to the frames. I think this is unnecessary though. I usually need to remove the entire lid to reach into my frame anyway. Instead, I just put something heavy on top of the lid if it's extra windy and I need to secure the lid.

You can insulate the frame a little bit by putting garden fabric underneath the lid and along the edges. Adding a lid to your frame might seem like a small thing, but it really makes a huge difference!

I will usually build something similar for my pallet collar beds, but with just a single batten across instead of four. I don't use brackets for these lids though, which makes them a little less long-lived than the lid I built today.

Read more: How to use pallet collars in your garden

Good luck building your own cold frame lid!
/Sara Bäckmo