Earlier this February, and after an extensive search online, I found a great second hand 8 x 6 greenhouse for £120 including delivery! A concrete base had been laid in preparation and I wasted no time in getting the greenhouse frame up and the glass in with the help of my friend, John. Here are my top tips for keeping a greenhouse warm in winter:
1. Insulate
The best way to ensure heat is kept in and electricity bills are kept down during the winter months is to line the greenhouse with horticultural bubble wrap. Horticultural bubble wrap is UV stablised, which means it will not deteriorate and can be used for several winters.
The 20mm bubble wrap I used also enables the maximum amount of light to reach your precious seedlings and plants – an important factor to consider when light levels are low during the winter months.
I purchased my bubble wrap and the alliplugs and spacers from Harrod Horticultural. The alliplugs and spacers fit easily into the greenhouse frame and ensure that the bubble wrap is kept at a good distance from the glass, thus creating a double glazing type effect.
2. Beat the cold with smart heaters
By the beginning of March, I was keen to start sowing both hardy and half hardy annuals as well as starting off my dahlias and cannas. I purchased a Botanico 2kW greenhouse heater from my local Wyevale Garden Centre. These heaters only cut in when the temperature goes below the temperature you have set and also have a frost guard setting, ensuring the temperature does not go below 5 degrees celsius.
Within a week or so the first seedlings were peeking through and it was all systems go!
Here is a picture of the greenhouse groaning with plants at the beginning of May. I even had to purchase extra shelving to accommodate my ever expanding bounty!