I have two gardens in very different locations and they are not behaving as I had expected in respect of responses to the oncoming winter. The first is a suburban garden and is about 500 feet above sea level. The second garden is situated towards the top of a hill in the Welsh borders with an open aspect (and consequently lovely views) at about 1000 feet above sea level.
With the encroaching cold weather and a few frosts I expected that frost tender plants in the hilltop garden would be the first to die back. However that has not happened. The oca, mashua and Jerusalem artichokes in the Telford garden succumbed to frost first – the top growth of the oca in particular melted away weeks ago. However on the hillside today I find that the oca is still relatively untouched by frost, the mashua is still quite green and looks to still be growing. The Jerusalem artichokes and yacon here have died back, but later than their suburban cousins.
Although the borderland garden is much higher and theoretically more exposed, the actual microclimate of the perennial vegetable patch is presumably much more favourable at this time of year. It is tucked in quite close to the house and is not all that far from next door. At the back it is bordered by the mixed hedge running along the road and to the front it faces south.
This is the first year of planting for the borderland garden and I certainly did not expect this difference. However it has got me thinking and open to the possibilities of trying to create specific niches for microclimates next year.
I have been out this afternoon to harvest the first of the roots, with fingers crossed that there would be something to harvest below ground. The patch they have been growing in has been an experiment from the outset, being constructed from branches, twigs, upturned turfs and, humus-y material from the nearby hedge. It was then topped through the summer with grass cuttings and hedge trimmings galore. For more about that click here. From a slow start the plants in it grew huge by the end of the summer.
And this is what it looked like by the end of October (the black plastic is next door):
I have not weighed them yet, but here are the yacon tubers gathered from the first plant today (there are a number of other tubers out of sight below the top one).
It has always been my experience that cold air moves like water, flowing down. We have very hilly countryside here, and those with gardens on top of hills get frosted later because the cold air flows down to the valleys below. I can walk down a steep hill in the evening when everything is cooling down and feel a big drop in temperature in just a matter of feet.
I’m glad the climate in your new garden is so much warmer. I’m excited to hear what that does for your Oca, Mashua, etc. when you harvest. High hopes for you.
Radiation frosts tend to form more at low altitudes, while high ground, even in the same valley can escape. Advection frost will get you though!