Cold frames and low tunnels are incredible growing spaces, enhancing what you can grow all year round. In the colder months they are exceptionally good for leafy greens and once it gets warmer peppers and melons really thrive in them. Making the most of them needs a bit of thought though. First lets take a look at the differences between the two.

<aside> đź’ˇ This chapter should be read in conjunction with my guide to growing under cover and my guide to making frames and tunnels

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The pros and cons of low tunnels and cold frames

https://youtu.be/dJxMDVLZH48

The pros

  1. Cold frames are more flexible, their lids can be easily removed and stored
  2. Cold frames can also be low tunnels, but low tunnels can’t as easily become cold frames
  3. Cold frames are easier to make, but more expensive, now that the price of wood has risen so much
  4. Cold frames are very robust, coping with extreme storms
  5. Cold frames are easier to keep cool, making them especially good for plants like spinach, that don’t like it too hot
  6. Low tunnels provide a superior growing environment in winter, trapping more heat
  7. Low tunnels are cheap to make, just a base frame, a few tubes and polythene sheet
  8. Low tunnels provide extra height, especially when fitted to a cold frame base, this makes them perfect for growing early brassicas and peppers in summer
  9. Low tunnels cope with snow and rain better

The cons

  1. Both cold frames and low tunnels tend to be a bit humid in winter, some crops don’t care, but lettuces tend to suffer and do better in a high polytunnel, with more airflow
  2. Cats and foxes like to jump on cold frame lids!
  3. Water can puddle on a cold frame lid, stretching the polythene, if it’s not positioned at an angle to ensure run off
  4. Low tunnels are hard to store, when not needed, but I find a good use for them all year round, so that’s not an issue in practice