Over the past couple of years, I’ve been dallying with the idea of making a hotbed. This year, the stars seemed to have finally aligned as we were given some flexible wood frames that I saved for a winter project.
The wood frames provided are essentially used as pallet frames for delivery of electrical goods. They are really flexible, and can be folded and put away easily when not in use and best of all, come in a standard size with a width and length of approx. 80cm x 120cm This makes them very easy to create a frame or ‘dutch light’ for. Additionally they can be stacked up in height which is great as hot beds need to be at least 60 cm to 90 cm high to generate the heat required.
If I hadn’t been given the pallet frames, then I would have probably tried to make a wood frame using pallets or any other wood off cuts I could source easily. There are a few you tube videos about this from Charles Dowding and a really nice old one by Jack First that I’ve used for inspiration. Given that it’s my first time doing this, I expect to learn a lot about what’s good or bad about them, but I’m excited nonetheless to try them out and see how many more seeds I can get going this year.
One last point- these hot beds are quite an intensive and time consuming affair. The main reason I am doing it, is because I have very limited space on my kitchen windowsill at home. Our home is north facing, so the options to start things off at home are few. I have experimented with a larger metal bookshelf next to a glass door but that resulted in a lot of leggy seedlings, and wasted effort. Lastly, the wooden pallet frames were really easy to work with and in plentiful supply, and free!
So we’ve only had to work on creating the top frame, making it a fun family project we could keep coming back to over three weeks (we kept having to stop and get supplies/ play football and have snacks!).
HOW TO MAKE THE PLASTIC WOOD FRAME:
We found that we needed the following items for each wooden:
- Wooden battens- 2 x 240 cm long for each frame. We cut these to size to create the frame.
- 16 x Screws to fix the frames together
- 2 x Hinges to hold the frame to the topmost wooden pallet
- Horticultural polythene
- Staples to fit the polythene to the wooden frame.
Process:
- Begin by cutting the wooden batten into 5 pieces to create the frame. We cut two longer pieces measuring 120cm and 3 shorter pieces measuring 80cm. The extra shorter piece is used to create a middle strengthening element to the wooden frame.
- Measure and make the holes to fit in screws. Ideally with some help, fixing the 2 outer shorter pieces first and adding the final short piece in the middle last.
- Affix the polythene, stretching it as much as you can to avoid water pooling in the middle using staples.
- Finally screw in the two hinges on the top most frame and the wooden frame is complete.
- Start to fill the hotbed with materials- horse manure and straw is often recommended. However I’ve got a free supply of ‘waste’ spent hops used by the local brewery and delivered at our allotments. So I only need to get some straw to add to it to get my ideal 50:50 mix that generates enough heat. You can also use chicken manure/woodchips as an alternative from what I’ve seen elsewhere (see this link)-https://www.ruralsprout.com/hot-bed
- Once you’ve reached the top, around 60-70cm high, it’s now time to add the growing medium or soil and compost. You need it to be around 20cm
- Once the hotbed is filled up, leave it for about a week to generate enough heat.At least 24 degrees(Centigrade) or 73 degrees Fahrenheit should do the trick.
- The hotbed is now ready to use, and for me I’ll be aiming to get some early season seedlings going. Wish me luck!
Update: The hot bed is actually hot! I touched the soil and it was warm, my thermometer gave a balmy 20 Degrees Celcuis reading on one of the hot beds! I can wait to start sowing.
Over to you, what do you think of the hot bed? Would you go to the effort of making one? Let me know you got on and what you learned