In summer 2018 we invested in two 22m long polytunnels which we use to over winter plants, start seedlings off and house young plants.
Maintaining a constant temperature inside the tunnel is difficult as we currrently do not have any heating system in place. Ideas for next winter especially, we are considering an indoor compost heap that will be very warm at the core and release heat even through the night when temperatures drop.
On sunny days it gets real hot and the soil warms up and retains its heat, and stays a lot warmer than it would outdoors which is where we find a massive advantage.
So although we did not install heating, we used various techniques to keep our plants on the safe side of winter. Mainly this was achieved by ensuring a complete seal of the tunnel, no gaps or breezes, and again, being hopeful!
Luckily for the plants there is no wind which is great for protection but does mean ventilation is required. We do this by opening both doors to allow a through flow of fresh air. We also have covered the mesh door windows with plastic but during summer they will provide a ventilation even when the doors are closed.
Late summer seeds grown and overwintered in the polytunnel
Seedlings that were started indoors under lights were transferred to the polytunnel throughout early spring
We were able to sow seed directly in the tunnel in late summer, giving us strong healthy and early spring plants. They were kept in a seed tray with a ventilated lid all the way through until temperatures spiked in Feb and it was time to pot up!
Bubblewrap placed on the benches underneath the seed/young plant trays gives them a little extra insulation.
February welcomes the first tomatoes of the season
March brought a little snow and a lot of wind
Plants that have been started off indoors are now flooding into the tunnel! Potting up, shifting plants, sowing seed directly and watering is the new norm. As well as sweating out and being haggered by the scorching daytime temperatures!
By the end of winter we have also managed to build two new raised beds connected by a trellis archway ready for some summer climbing plants including Passion fruit and Melon!
To continue this story see our next blog: First Spring in the Polytunnel