A Northumberland Alpine Gardener's Diary
This entry: 05 July 2009 by John Richards
Some Dolomite specials. Entry 120.
Back to the future
Home from another mountain holiday, this time to the Dolomites. This is the fourth time I have visited Selva in the Val Gardena, but we have not been there since 2001 and this is the first time I have been there without leading a Tour, a blessed relief I confess. Also, in retirement I am able to choose my dates, and we travelled two weeks earlier than on previous occasions.
In fact, despite some very cold weather in the first week (the tail-end of serious flooding experienced by parts of Austria and Hungary) the dates could not have been better, and we were able to see all our targets in prime condition, apart from Daphne petraea and Primula spectabilis which were well over (we travelled to Lake Garda one day).
Selva is a fantastic base, perhaps the best area for mountain flowers in Europe. There are snags. The town is perhaps a little too big for comfort these days, and the traffic is horrendous. Not perhaps in volume, but the many thousands (and I am not exaggerating) of German motor cyclists who drive over the passes far too quickly are both very dangerous and noisy, while the unbelievably athletic cyclists are equally numerous and dangerous, although much less noisy. It comes to something when one is passed in a car while driving down steep bends at 60 kph by a lady cyclist!
We saw many wonderful high alpines, and I may show a few in future weeks. To begin with, I thought we would start with the quirky. For instance, what about the marmot who has moved into a bijou, ready-made apartment? Weatherproof and well-drained, it only lacks central heating.
In my working days, one of my areas of interest was the pollination biology of flowers. One of the supposed great mysteries was what pollinated the extraordinary flowers of Physoplexis comosa, which have no obvious counterpart in the plant kingdom. I had always supposed it was long-tongued bees or bee-flies which probed the lantern-slits, while brushing against the stigmas and so achieving pollination as they approached the flower. I may well have been right some of the time, but here is incontrovertible evidence that butterflies (here the Pearly Heath) can be effective visitors too.
Staying with pollination for a moment, I scarcely doubted that the fragrant orchid, Gymnadenia conopsea, was pollinated by butterflies and day-flying moths. Indeed, Darwin said so, so it must be right! Nevertheless, I was delighted with this photograph of a Hummingbird Hawk-moth, which not only shows the proboscis probing the spur of the orchid flower, but pollinia from previous visits stuck to the bottom of the proboscis, waiting to be transferred to an orchid stigmatic cavity.
Two more plants from this holiday. It is now 25 years since a raw Tour leader advanced up the Vallelunga with his party on the first day, wide-eyed, innocent and pretty ignorant. My liquid retention was no better then than now, and as the breakfast coffee hit the spot I pleaded solitude and hit the bush. What I saw there caused a rapid return to the waiting party with the injunction 'there is something here you may want to see' (!!).
On subsequent visits, this population of the lady's slipper, Cypripedium calceolus has proved a reliable target, and so it was this year, but with a big surprise. Several plants, four certainly, had green tepals, not purple ones. We revisited the population the following week when the flowers were wide open, and they were still green. This is apparently known as f. viridescens.
Finally, for this week, something of a mystery. On my second visit to Selva in 1990, Ian Bainbridge informed me that he had discovered Primula tyrolensis on the Pordoi Pass the week before. This was a great surprise, not only because it was an extension of range northwards of about 15 km (not a great deal you would think), but because the site has been extremely thoroughly explored for a century or more and where the plant occurred appeared to be metamorphic rock rather than the Dolomitic limestone P. tyrolensis is known to favour.
Using Ian's detailed instructions, we found the plant in 1990, but out of flower. In 2001, a few flowers remained, but the plant was in poor condition. Nevertheless, I became convinced that Ian had identified it correctly.
This year however, the plant was in full flower and the colony had expanded considerably. There were certainly not less than 250 plants, surrounded by P. minima , which is common here, but which did not really penetrate the main 'tyrolensis' colony. I took dozens of photographs, which I have now had a chance of examine closely. I have come to the conclusion that many of the plants are indeed fairly typical of P. tyrolensis, such as the one shown here, although the leaf-teeth may be a little large. However, others are probably introgressed with P. minima as the leaf-shape of these is more intermediate. Perhaps because of this, the tyrolensis seems very vigorous, more so than the P. minima.
Despite the cold weather in Italy, CNN kept us in touch with the apparent heat-wave that the UK had been experiencing. I grew more and more apprehensive as our return date approached, expecting to find a massacre with hundreds of dried and shrivelled seedlings, show plants and a desert-like garden.
I could not have been more wrong, and despite some small attrition amongst the seedlings, caused by overwatering by the great irrigation system in the sky, I seem to have lost nothing, not even (yet!) Primula wattii, P. wollastonii, P. nanobella, Meconopsis sinuata and the other new goodies. Apart from dessicated bulbs, I had virtually emptied the 'dry' alpine house, and plants stood outside on the gravel path were in fine fettle. The scarlet flower is the suicide lily, Gladiolus flanaganii.
In fact we had been very lucky. It had been warm (but not anywhere the 32C experienced in London), but wet with many storms. The alpine house with automatic watering had been left full of plants, and with the fan off, but everything was in super condition. A slight leak to the watering system had left the greenhouse floor a bit wet, which might have helped! Serendipity! In fact, my main concerns were with the shady plunge which had been a little too warm and wet, with incipient signs of rot amongst a few androsaces and European primulas. These have been stripped of rotting leaves, dried out and returned to the alpine house for a bit. I think everything will be OK.
After my first visit to the Beima Shan back in 1997, I had always harboured an ambition to flower the wonderful Gentiana georgii. Seed has been offered several times in recent years and germinates well. Young plants present few problems, and I have overwintered them both in the alpine house and in raised beds and troughs outside, where I still grow a few. However, four years on I was beginning to despair of ever seeing a flower. Finally, it became clear before we departed that the remaining pot-grown plant which has never left the alpine house (and has remained in the same pot for three years) was going to flower. And here it is! Isn't it super?
Looking back on previous summers (and this is the fourth about which I have written), I find it difficult to identify subjects about which I have not written before. One such seems to be Corydalis elata, now at its best. This was in danger of being smothered by oak fern and the giant lily cardiocrinum, but it was lifted, divided and planted in new soil in the early spring (unlike the more familiar spring-flowering C. flexuosa it is spring dormant, summer-green). It has proved a good parent and Ian Christie in particular has raised his Craigton hybrids between the species, but I am fond of the species too.
Petrocosmea kerrii is flowering earlier than ever. Unlike the winter-flowering species that have become popular in recent years, this survived 10C last winter under glass without turning a hair. The rather damp shady floor of the alpine house seems to suit it fine.
I have, I think, mentioned that adaptable plant Geranium dalmaticum before, but its ability to thrive in dry stony sterile shade takes some beating, even if it is really best suited to open sunny conditions. Our front drive is a difficult place, invaded by tree roots, and the geranium is invaluable here.
More Dolomites next week, I guess!