Greenhouse heating

- 9 degrees when I went to work in the morning. A business partner who came from Tampere in the morning said that in the middle of the way to Helsinki at Hämeenlinna temperature went as low as - 19 degrees.
At 4 PM Helsinki city centre was + 1 degrees. And back to home when I took this frame 6:30 PM again - 9 degrees.
Heating is needed for our tomatoes.