The Nature of Frost, (and an update on the Tree Dahlia)

I moved to Robertson from Canberra, where, undoubtedly it is colder than Robertson. However, there is something different about the "cold" in Robertson. It is a wetter place, and so the cold seems to penetrate more.

Two days ago, we had a lot of rain during the day, then the clouds cleared off in the late afternoon. I know that always means trouble. For example, I was alert to the possibility of black ice on the road, the next morning.

What I had not anticipated was that the heater would run out of gas at 4:00am, and that Zoe, (the great softie that she is) would decline to go out and turn the switch from one gas bottle to the other - 30 seconds work. I was persuaded to go out and do the job myself, by Zoe thumping around the house, trying to get warm - a futile exercise, on such a cold night. Indeed it was the hot water running out when she tried to run a hot bath in order to warm up, which really triggered my decision to turn the gas tap over myself. Incidentally, I have an electric blanket, but until tomorrow's scheduled visit to Bowral, Zoe does not - she just has a cat to keep her warm. She has been promised an electric blanket, though. The cat will be ecstatic!

Anyway, I went outside, to find the switch for the gas tank, only to be surprised by hearing myself crunching over the grass (weeds, really). Odd, I thought - must be a heavy frost to do that. Next morning, I discovered that the source of the sound effects was that I had been crushing thousands of ice crystals, under the soil, as I walked just a few paces to the gas bottle.

Technically, these crystals which form in the soil are known as "permafrost", but my Northern Hemisphere friends will scoff at the application of that term to this little bit of ice formation, for it is not "permanent", or even semi-permanent. We aren't on the Arctic Tundra here. But what I was experiencing is quite different from a normal frost, where tiny particles of dew freeze on the surface of the grass, or soil. This was moisture in the soil freezing slowly, and, as a result, the crystals growing up out of the soil, and they lift the surface of the soil up to the height of the crystals, about 3 or 4 cms high. These crystals have great lifting power, and tiny pebbles, and small rocks will be lifted as the crystals beneath them form. Such crystals can, indeed crack large rocks, if they form within crevices in the rock, then expand.

Leo and Anni are entitled to tell me that I don't know anything about real cold. But it is cold enough for me, here in Robertson. It is also cold enough for Peonies, which was my primary criterion, when selecting a location when I moved from Canberra.

I mentioned last Wednesday the "Optimistic Nature of the Tree Dahlia". Great timing for that post. Have a look at it, on the morning of our big freeze. That was yesterday. Today it is showing even more damage, but you get the point - its growing season is over - for this year.

Oh well, it will have to start again next year to grow two metres tall, or more, before it will start to form its flowers, in late April or May. And, of course, it is destined never to set any seed, in Robertson. Poor thing. But I love the way it keeps on trying.

One could say that it is a metaphor for someone being treated for Lymphoma, really! No wonder I admire its stubborn hold on life.