A very heavy frost like the one this morning really sorts out the freeze-tolerant plants from the ones that will be destroyed by the formation of ice-crystals on both their outer surfaces and in their internal cell-structure. The simplest part of this to understand (for me anyway!) is the way some plants create a sort of ‘anti-freeze’ by accumulating sucrose and other solutes in their cells, which actively lower the freezing point of water, a bit like salt does when spread on our roads. They can also adjust their proteins and lipids with similar effect, while those that are destroyed by frost will be broken down into humus and other nutrients that enrich the soil. One way of helping some plants in our gardens survive frost, especially Camellias which flower early and whose beautiful flowers can be damaged by frost, is to plant them where the early sun will not fall on the plants and cause too rapid thawing. Conditions: Heavy frost, and unseasonably warm sun. Temperature: Max 11 Min 4C.
Winter Solstice: On this shortest day of the year, this is just a reminder that our smallest birds, the Wren, Goldcrest and Firecrest, unlike others of our birds that can switch to seeds and fruits when insects are in short supply through the colder months, rely on insects so the more untidy we are in our gardens and countryside, the better off they are. Insects will stay in the microclimate under leaves, in shrubs, conifers and dense foliage and in hollow stems and uncut grasses and flowering plants. In really freezing winters these small birds (you are more likely to see Wrens and Goldcrests in your gardens- I’ve only seen a Firecrest once and that wasn’t in my garden!) Somewhere they can roost, like bird boxes and hedges, also help. No wonder, with the loss of so many hedges our birds are under threat. Conditions: Mild with some sun after heavy rain. Floods and waterlogged land in the south and east. Temperature: Max 8 Min 5C.
Great Tits: as we approach the shortest day, and birds of all kinds have less time to forage, the desperate scramble for food becomes more crucial to their surviving cold spells of weather. Great Tits, our largest species of the Tit family, rely on seeds through these conditions. While most Great Tits stay roughly in their areas of birth, some do travel from higher to lower ground but they are spread through the UK so wherever you live, if you can put seeds and fat out it will help them and other small birds that lose more heat per body weight than larger birds. In harsh conditions Great Tits can need to eat up to 44% of their body weight in a day in sunflower and other seeds. (Who does such research?! )
Conditions. Cloudy and with rain on its way. Temperature: Max 12 Min 7 c.
Just when I think there is nothing more to be gleaned from our Joseph Rock Rowan, a beautiful and acrobatic pair of Bullfinches turn up and expertly gather some of the last, now bletted but obviously still nutritious berries from the very tips of slender stems. As the tree is about 15 feet away from the window, the views, in yesterday’s welcome sun, were clear and bright. We have two pairs visiting at present, which I know is very lucky- a function of being near a wooded part of Sheffield centre and the fact that we plant for wildlife and feed all year round. Conditions: a welcome spell of calmer, brighter weather. Temperature: Max 10 Min 8C.
Robins in winter– Robins are one of a few birds that sing throughout winter in the uk. This is because they are particularly active in defending a territory year round but scientists in Bristol believe that us feeding Robins through the winter helps. Birds have a complex mechanism to manage their fat reserves, and Robins will only sing through the winter if they are well fed enough. They appear to be able to assess when they have enough energy to sing in the day, so a ready supply of food, and warmer nights means they are more likely to be heard defending their territory by their beautiful song
. Another reason to feed our birds. Conditions: A spell of bright, sunny weather. Temperature: Max 6 Min 3C.