A North Wales Alpine Gardener's Diary
This entry: 24 July 2013 - Entry 7 by John Good
Be careful lest you get what you wish for!
After 9 months of more or less non-stop wind and rain (and snow!), and chilling winds from the Urals, our prayers for sun and heat were answered with a vengeance, and now we are praying for rain!! It seems hardly possible that it is only 3 weeks since the drought started, but it is the severity more than its length that has caused problems in the garden. We rarely get temperatures above 25 C in N. Wales but this July the daytime maximums have regularly been in the upper 20s, occasionally touching the unheard of 30C. As a rule I hardly ever resort to or need the use of a hose and sprinkler, and as we are on a water meter that is just as well, but this time I have been spending much of my time moving the sprinkler and dashing on mercy missions with a watering can to individual plants suffering from heatstroke . Worst affected have been the cushion saxifrages, whether kabschias or mossies, and despite my Florence Nightingale ministrations many have developed scorched patches which will not recover. Does one pull the whole plant out, take cuttings from the remaining good bits and start again, or carefully remove the dead rosettes (best done when the drought has ended and the full extent of the damage can be gauged) and fill in with compost or, if the resulting hole is a big one, push in a stone to fill the gap? Of course, if we lived in an area with more predictable summer droughts and high temperatures I would not have planted the saxifrages in full sun in the first place, but here in N. Wales such positions generally suit them fine.
Happily not all alpines are as prone to damage by heat and drought as the saxifrages, so let's try to be upbeat and talk about some of those that have flourished. Pride of place should perhaps go to Phsoplexis comosa, an easy plant here which belies it's reputation for being especially prone to damage by slugs and snails. As its ecology suggests, it is a crevice plant par excellence and in such a situation it is very long-lived in the garden, requiring no special treatment, I have never found it easy to propagate either from cuttings or seeds, does anybody have some advice for me and other readers who have been similarly unsuccessful?
The campanulas are close relatives of the Devil's-claw rampion (Physoplexis) and they too have been very little affected by the drought. C. kemmulariae is a good species with nice dark flowers that will spread steadily but can easily be kept in check. Also spreading into mats, but not really sufficiently vigorous to be a problem to other plants with which they interweave, are C. arvatica and its lovely pure white form, one of my favourites in a much-loved genus.
More aristocratic and meriting a choice position in a trough or crevice garden is C raineri, which also has an equally choice albino form. These are easily increased by taking off rooted pieces in spring or autumn and potting them up in a gritty compost mix.
A group of plants that really come into their own in droughts are those with silver foliage, the fine silky hairs limiting water loss and reflecting the hot sunshine, causing them to shine in a way they never do when the clouds gather. My favourite of many such plants is Artemisia schmidtiana 'Nana', of which there are a few clones available in the trade. It needs quite a lot of space as it is a fairly fast grower and is not a plant that you want to have to cut back to often or too hard. Cuttings root readily in spring or autumn.
Altogether different, and what my dear late Mother would probably have called "vulgar but irresistible", is Calandrinia ? umbellata (is this the correct name??). It is less silvery but has quite fleshy leaves that are well protected from dessication by a covering of silky hairs, and when those astonishing silky magenta flowers open in the sunshine it is a real 'wow' plant. It is a close relative of the lewisias and similarly easy to raise from seeds, which in this case are produced in capsules which split longitudinally rather than opening at the tip, the chief distinguishing feature between the two genera.
Also surprisingly drought resistant, until one looks closely and discovers the dense covering of hairs over the whole plant, is Androsace lanuginosa, a pretty small-scale Himalayan trailer for a trough or crevice. I have never tried to propagate this plant - any suggestions?
A couple of N. American lilies
I have a bed shaded by a high wall that only gets sun for a few hours in midsummer and which has the priceless advantage of soil that NEVER dries out - even now I have not had to apply so much as a teacup of water to any part of it. In this bed, which also provides a good home for meconopsis, irises which favour wet soils, bog primulas and the like, the N. American bog lilies thrive. Pride of place goes to the common-or-garden Panther lily (Lilium pardalinum) which grows to six feet and flowers very freely - this clump is c. 10 years old. According to Woodcock and Stearn in their wonderful book Lilies of the World, the bulb is (was?) so common in wet areas in California that the Chinese living there developed a liking for it as a vegetable and collected it in the wild for this purpose, a practice which we trust would not be considered PC in these enlightened times!
Much less vigorous, but otherwise similar in most respects, although the flowers tend to be less profusely spotted, with shorter, thicker styles, is L. vollmeri, which has a much more limited range in the wild where it always grows in bogs. It grows to about 50 cm, generally has only one flower per stem, but is a real charmer which it is well worth a good deal of effort to obtain and then grow well.
Orchids seem to have a universal appeal not only to gardeners and botanists, but also to the general public. I have to confess to possessing a very small orchid house which I keep at 15C minimum in which I grow a range of sub-tropical orchid species and a few hybrids, but it is not those that I will mention now. I have a few dactylorhizas but the two that do best for me are D. x grandis (D. fuchsii x D. praetermissa) and D.''Bressingham Bonus', which appear below in that order. They grow steadily into largish clumps that are easy to divide in spring as they start into growth, or in late summer, when they have just died down. They seem to flower just as well in light to medium shade as they do in full sun.
Finally for this month we have a real stay-a-bed which this year has lain in even longer than usual, giving me a real scare as a result. I speak of the delightful Arisaema candidissimum, which usually makes its appearance around midsummer's day but which this year did not appear until this week, overnight on Monday in fact! My smallish clump is really in too dry a place, but I mulch it well with well rotted garden compost as soon as the flowers pole through and this keeps it reasonably happy. I must excavate around the clump later this year and take off some of the spare tubers and plant them in a moister spot.