Monday, December 23, 2013

How green is our winter

The tents of an invading army of Hobbits? The emergency accommodation put up to welcome the army of Romanian guest-workers our idiot government are trying to convince us are about to descend?
No, the leaves of Gunnera manicata all heaped up by Wisley staff to protect the crowns. Just in case we have a hard winter.

I was down at the RHS garden in Surrey last week to do some work in the library and had a quick look around the garden. So far we have hardly had temperatures below freezing, and I have never known trees hang on to their leaves so close to Christmas. It really feels like a phoney winter.

The inner part of the seed cases of Lunaria rediviva. One of the best seedhead plants.

Fruit - mini-apples, on Malus hupehensis. Berries/fruit and seedheads are the classic elements of the early winter garden, now joined of course by seedheads and grasses. This stroll around Wisley however is a reminder of how green winter can be, especially if temperatures do not dip too much.  A good opportunity to reflect on just what sort of a climate we have and how that impacts on plant selection. You see, for some time, I have realised the rather counter-intuitive notion that we have more in common with a Mediterranean climate than a continental one even though most of our garden plants are from regions with the latter climate. Mediterranean winters are cool and wet, a bit like ours are a lot of the time, even before the current run of mild winters started in the 1980s. We can have the luxury of green foliage for quite a lot of our winters as a result.

 Things like Acanthus mollis, Mediterranean perennials which make a great leafy show right now. The paradox is that many (all?) Mediterranean plants will make active growth at lower temperatures than those from continental climates - the risk of growth being zapped by hard frosts is low. A walk around a garden now can tell you a lot about what climate zones plants are from.

Blechnum chilense, a Chilean fern also used to mild winters. A great winter foliage plant if you can get away with it.

Geranium palmatum, from the Canaries. We can do well with these plants from the middle Atlantic Isles, with their moderate climates, not too cold or hot.

And a libertia - foliage still fresh and green - indeed evergreen in most winters. From Chile and New Zealand - again that moderate, equable, climate.

Looking a bit ropey, but not completly dormant, Gerananium macrorrhizum from the Balkans, an area which gets cold winters and a lot of snow but which sometimes has milder spells, so it helps being able to photosynthesise in warmer periods.

A nepeta (catmint), another genus with quite a few from the Mediterranean. We tend to think of plants from the Med as being not hardy, but much of the region gets occasional severe winters, especially the eastern part when cold air masses can come down from Russia and central Asia via Turkey.

Now, the borders which Piet Oudolf designed in 2000, looking fantastic right now, but hardly any green. These are plants from continental climates for the most part; for their own protection they have to totally shut down for the winter, and not come out of hibernation until temperatures are relatively warm which means all danger of frost is past. I find these grass, seedhead combinations incredibly beautiful, all the more so for their stark contrast to the amount of green elsewhere at this time of year in a garden like Wisley.

But what is this? Greenery amongst the not-anymore-Oudolf borders. Piet is no longer involved with overseeing these borders, which is a shame, as they do need a very particular kind of guidance -
certain people on the RHS General Council have expressed disatisfaction with the way things are maintained here too "they just don't seem to get it" she said. And new plants - such as Pennisetum macrourum, a South African species with nice heads but an aggressive spreader. Didn't anybody know that once this plant is in, it will run and run and completely blur whats left of the design? Good plant - wrong place. One of many South Africans that seem to be doing very well here, like the Diearamas that seed madly in my own garden.

Box and grasses - I think this was Anemanthele lessoniana - don't they look good together? Surprised you don't see this more often, very much the old and the new together. Again, box and most other evergreen broadleaves are part of that flora of 'Atlantic' Europe (actually we should include north-west Africa in here too) , plants of mildish winters, species of the western Mediterranean, hardy enough in normal circumstances but not so capable of taking the constant very cold winters of central Europe. Ivy is another one, the semi-evergreen bramble another.

Being aware of all this winter greenery gives me a strong sense of geographically where we are, on the fringe of Europe, with connections to all those other places our plants come from where winters are mild and occasions to grow (albeit fitfully) rather than hunker down and hibernate.

Having 'the holly and the ivy' is something of a luxury for us, living where we are. A green element in our gardens I wouldn't want to live without.


Roger Brook - No Dig Gardener said...

Very insightful post Noel. I have noticed my own Acanthus mollis looking good this winter.
I loved your description of the inverted leaves of gunnera as shelters-which they are of course for the crowns of the plant - but your pun about for fellow europeans. Every time I read my paper I am ashamed of our government!

Panayoti Kelaidis said...

I must try and visit Wisley in the winter--I've always done spring and summer and once the fall: it is one of my favorite gardens anywhere, and such a treasure trove of gems. Thanks for the glimpse in the quiet season!

Jane said...

But what about all the other wonderful glittery broad-leaved evergreens we can grow - pittosporums, myrtles, skimmias,phillyreas, euonymi, camellias, hebes, azaras - so many more. All you new perennialists wax lyrical over a few ragged acanthus leaves but there's a whole world of emerald shrubbery which we now neglect. Continental gardeners can't have them, we should make the most of shiny varied greens in our milder winters specially in town gardens.

David Ellis said...

I have not been to Wisley for a number of years, thanks for reminding me how much I enjoyed it and that I really should make the trip again as it really is not that far from my home in Kent.