Tuesday, 4 April 2017

an evening of alpines

This may be a brief post, as I was late back from the garden club meeting.  The talk was about alpines, and the lecturer had a lot to say about them growing in the wild and in gardens.  It was interesting, but lasted an hour and twenty minutes, which is at least twenty minutes longer than most people can concentrate.

Once he got on to the cultivation of alpines I realised how much I already knew, in theory, although in practice I am not awfully good at it.  I could blame the fact that the top of the garden where I try to grow them is almost pancake flat while he said they were much better on a slope, but I think the real issue is that the sand does not make a very good approximation of an alpine scree.  In spring when in nature they would be irrigated by the snow melt, most years in the Clacton coastal strip the soil is already getting dry.  And there is no protective blanket of winter snow to insulate them from frost.

There are lots of other ways of growing alpines besides in the ground.  I do have a few containers, though I use terracotta pots rather than making my own imitation stone troughs out of sand, cement and peat modelled around a cardboard box.  I have already empirically discovered the importance of good winter drainage and not planting anything that runs underground.  But most of the other methods are beyond me.  I am not going to buy tonnes of rock to build a rock garden, nor broken paving slabs to build a crevice garden, nor am I going to start constructing dry stone walls or use them to create raised beds.  I couldn't afford the materials, Essex is not natural stone country and it would look silly and out of kilter with the rest of the garden, and it is not going to happen.

And I wouldn't know where to source peat blocks.  The sad thing is that according to the lecturer, peat blocks are cut from the top one or two feet of peat covering bogs which are going to be mined to fuel power stations.  The surface layer of peat is not dense enough to use as fuel, but if it isn't sold to gardeners that doesn't save the peat bog, the top will simply be burnt off.  The blocks will last for decades in the garden without breaking down, as long as they are shaded and never walked on.  But garden use of peat is a sensitive subject, and I have never seen peat blocks offered for sale. Nor tufa, except by one firm online I'd never heard of, and something about their website made me reluctant to risk paying them money, let alone the large amount they were asking for very small pieces of rock.

Still, I liked the sound of Ashwood's Carousel series of Lewisia.  Apparently they will produce repeat flushes of flowers instead of only one, and they can cope with moisture in their crowns without rotting, which is the problem with most Lewisia.  I have been trying to get over that problem by growing them in terracotta herb towers, though I do bring them under cover for the winter and water them sparingly, and can report that 'Little Peach' and 'Little Plum' both made it through with no losses.  Actually, L. cotyledon 'Snowstorm' which I grew from seed has survived for over six years in an ordinary clay pot with a top dressing of grit.  The plants were beginning to look stunted and unhappy about a year ago so I broke down the group of four, potted them individually with plenty of grit, and grew them on in the greenhouse until they recovered.  I have just regrouped three of them into a bigger clay pot, and two are flowering.  So maybe Lewisia are not so rot prone as all that if you live in a dry part of the country, and keep them under cover for the winter while being very stingy with the watering can.  Repeat flowering would be nice, though.

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