Wednesday 18 September 2013

Cast in Iron

When I say cast in iron, I should perhaps emphasize that I am thinking of plants that resist drought. This in turn needs to be qualified with the warning that no plant is cast in iron since it is probably true that anything recently planted will be in need of tender loving care, but especially water, for the first year or two. And then one final codicil that some plants that resist drought are not so good at resisting cold and wet; so it is extremely complicated. That said in April 2012 I bought from Mme Spahl's nursery near Jegun three acers - A.discolor, A.Pacific Sunset and A.truncatum - and I have to say that they have done remarkably well with the minimum of attention. This has surprised me for two reasons. One they were rather larger than the trees I normally buy - about 1.5 meters - and usually large means more water in the years after planting. The second is that they are acers, and I have always thought that Acers in Gascony are difficult: too much sun and not enough acid soil.  Clearly I am wrong, but I do not think that one can put all of them in the cast iron category. For instance the japanese acers - A. palmatum - a huge and I have to say very attractive group probably do not do since they do require more shade and more acidic soil than most of us can provide, though of course if you are prepared to water often they can always be put in pots. That still leaves a very huge choice, so huge that my only advice is to consult the books and catalogues, the Adeline catalogue and the 'Arbres et Arbustes' of Les Pepinières Botanique de La Preille being particularly useful. Apart from the ones I have already mentioned I can personally vouch for A. Oliverianum, not I see mentioned by La Preille which is surprising. It is a most attractive small tree, resembling in many ways a Japanese acer and with the same attractive autumn colouring, though that is a feature of almost all acers. Mine flourishes, despite an attack by deer, in an especially dry spot, though under an oak canopy, so there is some shade.

As for oaks they are at least in the Gers our most common tree and the choice is immense, so difficult to do justice to them here. But we are talking cast iron, and not all of them come into that category. For instance one that is commonly sold in Gascony, Quercus palustris, or chene des marais, requires, as its common name suggests, a good deal of water to do well. In fact it comes from America as a lot of the highly autumnal coloured oaks do, and quite a lot of these prefer a fairly humid, and in some case soil on the acid side, for instance one that is quite readily available, Q.velutina.. On the other hand nothing ventured nothing gained.  One that has always grown well for me is Q.schumardii, and while La Preille suggest that it is happy in dry they also suggest that it prefers a slightly acid soil which is not the case in our garden.

So far only two families of trees, and not so many that our cast iron, so I need to push on a bit faster. Trees that I have often praised in these blogs are Pistacia chinensis and Pyrus calleryana Chanticleer and Red Spire, so all that I will say here is that they virtually cast iron. A tree that I do not think that I have mentioned is Melia azedarach. This is a most attractive small tree with almost fernlike foliage, small panicles of lilac flowers which are sweetly scented followed by berries.  What is curious about it is that it looks as if it might require a lot of water but since like the lagerstroemia it hails from China and India the sunnier it is the more it flourishes.

Finally since it is not all that well-known, and is perhaps more of shrub, though a large one, rather than a tree, I will mention Xanthoceras sorbifolium. This has attractive sorbus like leaves which colour quite well in autumn, and flowers early in the year which resemble slightly smaller horse chestnut candelabra.

In a future blog I will try and tackle cast iron shrubs, but before closing this I would like strongly to recommend that you visit Les Jardins de Coursiana, very close to Le Romieu which in turn is to be found roughly speaking between Condom and Lectoure. To my shame I never got to it last year, but following two recent visits I can only say that it is looking a million dollars. How Mme Delannoy does it I do not know as apparently she only employs one gardener though there is a husband and various children lurking. What has particularly struck me is her use of colour using a very large palette of annuals or semi-tender plants, especially dahlias in great profusion, but also impatiens, tithonias, verbenas and much else besides.Also featured is a plant that in Gascony I guess can be called a hardy perennial, for it has certainly survived very happily in this garden for two or three years. She calls hers Ruellia Rio Grande - incidentally there are plants available for sale - but the more important thing in my view is to make sure that you have a tall variety of around a meter in height with normally dark blue flowers, which I think is R.brittonia  rather than the smaller variety with pale blue flowers which I think is R.humilis. I have both, but for impact it is the former that wins, just as for impact Les Jardins de Coursiana are an absolute winner.  Moreover you will find there all the trees mentioned in this blog, and many hundreds more, since not only are there gardens but also an arboretum of some importance.