By a miracle of nature, even though the temperatures are above freezing, there has been a light dusting of snow for the last 12 hours or so. There has also been a warning of black ice on the school playground.
However, the nasturtiums seem unaware that lower down is on the cool side. It’s great to see them still and I can’t help but marvel at their resilience.
At the same time, I am puzzled that they soldier on when the hugel beds without vegetation on them (in fact any bare soil) is clearly cool enough to enable snow to remain. I’m therefore wondering if plants increase the air and/or soil temperature in their vicinity – at least in winter. It certainly can’t be decomposition in the hugel beds themselves with these being covered in a dressing of snow.
The following post doesn’t answer all my questions but explains some of what is puzzling me: http://www.canna-uk.com/root_zone_temperature_and_plant_health