A Northumberland Alpine Gardener's Diary
This entry: 14 April 2008 by John Richards
Northumberland Diary. Entry 70.
Snow, snow, quick, quick, snow
After the Chesterfield Show, now more than a week ago, we continued on southwards to stay with my mother in Reading. Next morning the 'deep south' revoked our expectations with a considerable blanket of snow. This persisted most of the day in arctic temperatures; long enough to take some photographs. It was curious that despite air temperatures well below zero, the magnolia and camellia flowers that carried quantities of wet snow were not subsequently frosted. Possibly the thaw donated latent heat sufficient to protect the flowers, analogous to the effect of spraying of fruit orchard blossom before a frosty night.
Later we went for a walk through the University of Reading campus to the Harris Garden. It was great to see Primula denticulata in this setting; a authentic alpine look! Primroses, P. vulgaris, also looked great under snow. I have seen them like this in March in the foothills of the Italian Alps.
The Royal Garden
Later in the week we spent a day at Saville. I first extolled the virtues of this wonderful garden late last summer. As was the case at Kew, the Japanese Primula kisoana seems much easier to grow here than in the north of England, and forms great mats, together with various forms of its compatriot P. sieboldii.
I shall use the next few photographs to luxuriate in a few of Saville's special features. Firstly the wonderful lysichitons, white L. camtschatcense, yellow L. americanum and their cream hybrid, followed by Pulsatilla vulgaris, Uvularia grandiflora, Sophora microphylla 'Sun King', Acer palmatum 'Corallinum', and a general view of 'winter colour'.
A dearth of rhodos
During the last week I have been able to visit several notable rhododendron gardens, not only Saville, but Howick on the Northumberland coast, Moorbank in Newcastle and some private gardens, including my own. I can never remember such a poor year for rhododendron bloom. Granted there have been late frosts, and many species are yet to flower, but the original bud set was also very poor on many. To take a single example, my mature Rh. 'Elizabeth' has covered itself with sealing-wax red flowers for every one of the last 16 years; this year, not a bud! Exactly the same was true for the Rh. barbatum I featured last spring.
I suspect that this poor showing has two reasons. Last year the flowering was unusually good, and most flowers did not get frosted, resulting in good but strength-sapping seed-set later in the year. Second, the summer weather was so poor before bud-set that the season's growth was insufficiently ripened.
While we are discussing matters climatic, I spent some of yesterday going through the alpine houses and interring casualities, now that it is clear for which subjects the damage is terminal. Last winter was the hardest we have suffered since 2001, the mercury dropping to -10C on several occasions. Also, recent visits to South Africa in particular had caused me to attempt (mostly from seed) a number of subjects of dubious hardiness, and these had been deliberately placed in the alpine house that has no auxiliary heat (but better light). Some have done well; several Dieramas including D. pauciflorum, D. luteoalbum, D. trichorhizon, Hesperantha woodii and Nemesia rupicola (which however did not survive the wet outside). However the toll has been severe and the following list is of those I am fairly sure died of cold, rather than of any other cause.
Anigozanthus humilis, Babiana sp., Cyclamen africanum, C. graecum (others of this species survived), C. pseudibericum, Degenia velebitica (just survived outside however), Dierama ambiguum, D. jucundum, Hesperantha baurii, Stylidium graminifolium, Weldenia candida, Xerophyta viscosa.
I note these, not least because some of these subjects are becoming popular on the showbench, especially Weldenia and Stylidium. I am particularly concerned about the latter which is a low-country Australian which probably never encounters frost in most of its localities, is not hardy, and yet has received the ultimate accolade of our Society, the Farrer Medal. I rest my case!
The tufa bed
My last contribution was written just before I was about to attempt to build a new bed using home-made tufa. Before we left for the south, I was able to finish this in three sessions; one to clear the site of plants and weeds and dig it over thoroughly (plants were stored overnight, no frosts then, in used 'dumpy bags' that gravel and sand is brought in); and two to build and plant.
The first photo shows the first four 'key-stones' in place.
I can't remember now what the hammer and stone chisel were used for!
The next two photos follow progress as the bed was built up and filled in. The compost used for filling was old potting compost with some added slow release fertiliser (see 'The Alpine Gardener' 75: 438).
Finally, here are a couple of views of the bed finished and partially planted; top-dressing has been provided by artificial tufa 'rubble'. On the whole I am quite pleased with the effect. At least it looks like no-one else's efforts!