Kent Alpine Gardener's Diary
This entry: 30 May 2014 by Tim Ingram
May in the garden
A careless shoe-string, in whose tie
I see a wild civility:
Do more bewitch me than when art
Is too precise in every part.
(Robert Herrick - Delight in Disorder)
By May the garden both fills with colour and variety and at the same time begins to run away from the gardener. Many gardeners hardly wake up until the late spring which is why the earlier flowering alpine and woodland plants are so fascinating to anyone who really knows plants. But May is an incredible month in the garden, so this diary entry will give it its head. This is when the garden really comes together, so it is hardly surprising that it is when Chelsea also flies its colours.
I have shown several pictures of gardens belonging to members of the Kent AGS Groups, and here is another from a past member, Tom Wood VMH. Tom is a plantsman and nurseryman of international repute and has the most amazing of gardens with extensive collections of trees and shrubs - in part grown to provide seed and propagating material for the nursery - and these are just a few examples.
The genus Michelia, very close to Magnolia, is often thought of as relatively tender, but this species, M. dianica, has grown through the harsh winter of 2012, and long cold spring of 2013, and makes a fine shrub for a sheltered spot. It tempts me to try one or two of the smaller species or varieties in our garden, and they are particularly beautiful in bud as well as flower.
We have grown and lost Jovellana violacea, a Chilean 'calceolaria', but this is such an intriguing plant that it would be well worth growing again in a more carefully chosen spot.
Much of the garden is on moist acid and sandy soil, perfect for ericaceous species and many good autumn colouring trees and shrubs such as dogwoods and maples. The rhododendrons are magnificent even when you have no chance or space to grow them in your own garden, and often almost as striking for their foliage as flowers.
High mountain species are more possible to suit in a smaller garden in carefully prepared soil or troughs. I am fascinated by the fact that they often have distinctively scented foliage which both Gwendolyn Anley (AGS Bulletin Vol. 8, p. 125, 1940) and the contemporary grower Rachel Lever have mentioned. These smaller ericaceous plants have huge potential in the garden, let alone than when exhibited at the Alpine Shows.
In our garden at the moment a much smaller alpine calceolaria, C. tenella, is particularly charming. The genus as a whole is nearly purely S. American in distribution and is comprehensively described by John Watson in the 'AGS Encyclopaedia of Alpines' - and more recently in the 'Flowers of the Patagonian Mountains' by Martin Sheader. Calceolaria integrifolia is an excellent and free-flowering shrubby species which has grown well in our dry south-east garden, except through the coldest of winters, so a number of others would be worth trying if and when available to gardeners.
Calceolaria is restricted to S. America (and Mexico), but the closely related genus Jovellana, with only three or four species, has a disjunct distribution in Chile and New Zealand, of great interest to the plant geographer.
Calceolaria tenella is a plant for a cool soil which stays moist throughout the year, and we grow it at the shady base of a raised alpine bed in pure gritty sand along with other plants such as dwarf willows and the cushion forming Bolax. Mostly though our garden is much more suited to dry-land alpines and the following are a few examples flowering now.
Thymus 'Peter Davis' is named for the famed botanist and driving force behind the epic eleven volume 'Flora of Turkey', and it is an excellent and neat plant. Turkey is a treasure house of alpines and bulbs and the second picture shows one of many small centaureas, C. drabifolia, grown from seed collected by Mojmír Pavelka. Add to this species of Acantholimon, Aethionema, Campanula, Dianthus, Hypericum, Linum, Salvia, Scutellaria and Veronica - amongst many others - and you have an idea of the richness of the alpine flora of this region.
From Greece and the Balkans, equally as rich as Turkey floristically, come so many more good plants: these are just a few examples. Aubrieta glabrescens is the rarest of the genus, endemic to Mt. Smolikas and collected by the MESE expedition (see John Richards' diary entry 149); Ramonda nathaliae comes from S. Yugoslavia and N. Greece by comparison with the Pyrenean R. myconi which is more familiar in gardens, and from JJA seed we have raised many plants, a few with pure white, or in this case soft-pink flowers, that we must propagate vegetatively; and Linaria dalmatica, a very easy garden plant less often seen than it deserves and not self-seeding in the way that L. purpurea does in British gardens (although in the hotter states of the western US it has proved an invasive weed).
North-west Africa, the fabled Atlas Mtns, give plants such as Convolvulus sabatius, relatively tender but well worth giving winter protection (and good for coastal gardens) and the rare Catananche caespitosa, one of those plants that must be hardly known of outside Botanic gardens and the specialist alpine and rock garden societies.
Finally, and flowering nicely in a trough at the moment, Globularia incanescens from the Italian Alps.
None of these are especially difficult to grow and are excellent in our drier climate in the south-east of England, but how many gardeners will have discovered them?
The Mediterranean and similar climatic regions, however, provide many other plants which are of more universal appeal. The helianthemums, stalwarts of rock gardens everywhere and superb on dry banks and walls, can be remarkably colourful - this is 'Fire Dragon' ('Mrs Clay') which may only be surpassed by the brighter orange-red 'Henfield Brilliant'.
Well over 200 cultivars of helianthemum have been selected over the last century (ref: a list given to me by Alan Robinson whilst he was at Wisley), very many like 'Fire Dragon' and the tried and tested 'Wisley Primrose' and very lovely 'Wisley Pink' ('Rhodanthe Carneum') dating from the 1920's. 'Henfield Brilliant' is more recent (1973). Few really stand the test of time as vigorous garden plants but they are so loved that very many old cultivars and seedlings must grow in gardens dotted about the country and are still listed in the Plantfinder, including many quite striking 'doubles'. By comparison smaller species such as H. canum and H. lunulatum are rarely seen in gardens - an indication of how garden selection inevitably is based on colour and show rather than more botanical interest, despite the fact that these latter can make good free-flowering plants too.
Such plants can combine very effectively, as Beth Chatto's dry garden exemplifies better than all others, and they have always been features of our garden since it was started in the 1980's. The weather can cause attrition and some are relatively short lived but many are easily propagated and replaced, and they give the garden a very distinctive air, particularly suitable in our hot and dry summers on the N. Kent coast. These are are few examples of wider garden scenes now and it is easy to imagine gardening like this on many different scales from the rock garden to the maquis and chaparrel, depending on the space available. For the alpine gardener sand, scree and crevice gardens are obvious extrapolations and I will show pictures of plants on our new 'Mediterranean' raised bed in a future diary entry.
Oenothera stricta, from Chile, is a biennial or short lived perennial and given an open gravelly soil will self-seed reliably and is an exceptionally beautiful and graceful plant, as attractive for its fading orange flowers as for when they are fully open. This serendipitous habit gives it especial appeal when it combines with other plants such as the example shown with Phlomis 'Edward Bowles' and the Californian Mimulus aurantiacus.
Elsewhere another phlomis, the soft-purple flowered P. italica, grows with Convolvulus cneorum, the S. African Geranium incanum and a curious (and in vogue) Mexican umbel, Mathiasella bupleuroides, named for the botanist Mildred Mathias of the University of California, who has made a close study of the American Apiaceae. In this picture too you will notice the large leaves of Echium pininiana. In rare mild winters dropping no lower than -4 or -5°C this plant survives and flowers, setting copious seed which carries on germinating for at least a decade from its last flowering (and probably considerably longer).
Our front garden is especially colourful with such plants at the moment: blue Moltkia x intermedia stands out along with self-sowing asphodels and Euphorbia ceratocarpa (perhaps the longest flowering of all plants in the garden). The striking and rarely grown umbel Thapsia maxima, grown from seed given to us by friends who regularly visit Portugal, is a typically transient Mediterranean species, long lived but dying down rapidly after flowering and setting seed in early summer. Behind it grows the 'Californian Firecracker' Dichelostemma ida-maia, a remarkable and reliably hardy bulb.
And in a warm corner the Rosaceous shrub Rhaphiolepis umbellata is particularly free-flowering and showy.
Few gardeners will grow such a range of plants but I should re-iterate that we grow them as much as a resource for propagating material and seed as for their ornamental worth or botanical interest. Unfortunately specialist nurseries don't readily attract custom in this age of Garden Centres, Supermarkets and Ebay, despite ostensibly having a more educated, sophisticated and mobile audience. So we have to combine at specialist plant sales such as the Alpine Shows and large gardens; for example at Godinton Place in Kent. Here there is a large walled garden, impressively planted but with an old alpine house which I would love to pick up and place down again in our garden. It has some interesting plants growing in it but they by no means emulate the craftsmanship of the alpine house itself, and it seems rather wasted.
The mild winter has enabled good flowering of Melianthus major here (normally cut back to the base by even moderate frosts). The flowers of this plant are held in showy spikes, but in the related - and much hardier - M. comosus they are hidden amongst the foliage and their striking red colour is probably attractive to small birds.
A very different plant, much more familiar to alpine gardeners, Podophyllum, also has flowers hidden under the parasol of leaves and is just coming into flower now. This will often set good seed in the garden, producing large plum-like fruits but I wonder what pollinates these flowers?
May is an amazingly rich month in the garden even if you don't have a view as picture book as Godinton Place or less of a Show Garden than Chelsea.
Despite the apparant wealth of garden plants listed in the Plantfinder, most gardens hardly touch on the real breadth of the Plant World, and certainly not natural species rather than hybrids and cultivars. The Plantfinder was originally devised by a member of the Hardy Plant Society, Chris Philip, in a quest to discover sources of unusual and rarely grown plants. It was edited by Tony Lord VMH and first published in April 1987 with the support of the then President of the HPS, Jack Elliott VMH, also one of the most well known and respected members of the AGS. Specialist garden societies and nurseries have always been at the forefront of maintaining the diversity of garden plants. But while we may be a nation of gardeners to borrow from Christopher Lloyd we are not necessarily all truly adventurous gardeners...