The trouble with Latitude

[charlie]

As this is a UK based forum we are all dealing with much the same, those of us in Cornwall at 50 degrees (mine is 50 degrees 26 mins) having a slight advantage but during the winter months when the sun has a southerly declination (currently above 20 degrees south) it leaves us with a midday maximum altitude fr the sun of just 16 and a bit degrees at its worst. Although the run up to its lowest point on the 22nd and 23 December is not normally the coldest part of the year it sure is the gloomiest! Still only three weeks until the sun starts its journey back. Personally I always found living in the tropics, particularly somewhere like Singapore close to the equator very hard to come to terms with, the early nights with a rapid change from day to night leaving me missing those long summer evenings (even if you do have to put a jumper on!)

The trouble with the above its fixed, nothing can be done to mitigate it apart perhaps from angling greenhouse conservatory roof glass so what little sun and heat there is in winter does not just reflect off, I think the Victorians reckoned 43 degrees the best angle but I have never seen the reason laid out in numbers. So while we are fortunate in having the Gulf Stream and sea around us which helps with temperature and we can use our low animal cunning to make best use of micro climates, indeed even deliberately seeking to create them if we can, there is unfortunately nothing we can do about low light levels, which brings me to ask what groups of plants from lower latitudes have folk found that appear able to cope with winter cold but struggle with the low winter light?

[kGarden]

Our house is a Passive House - designed to make the most of the Latitude. Roof overhang on the South side keeps the high Summer sun off the windows, and the heat out, whereas in Winter the lower sun comes in under the overhang and helps warm the house.

The East and West elevations are a problem in summer - the summer sun is hot in morning and evening, but also too low for any overhang to compensate for. Probably the right answer would be shutters, as they have in Spain etc., but I've planted a deciduous pleach on the East side, which lets the light in in Winter. However, not realistic as a solution for the upstairs windows as height would be a nightmare to maintain.

Passive House has a maximum heat requirement of 10W / sq.m - so for an average 3-bed house that's equivalent to a one-bar-fire - for the whole house :) - when the outside temperature is well below zero. If we turn everything off, lock up and go away for the day in mid-winter the house loses maybe 1C in 24 hours, and maximum Summer temperature in the middle of a heatwave going on for several weeks, like 2018, was 25C :) No Gulf Stream benefit in East Anglia ... the next thing at our elevation to the East is the Urals ...

[charlie]

As we battle to stop our 300 year old heap returning to the materials it was built from (cob) you can only imagine how much I would love to be able to start again and build something that does not leak heat for a past time!