Spring may bring fine flowering show

Press, 18 June 1982, Page 11

Spring may bring fine flowering show

O DIARY Ji

Derrick Rooney

Many rhododendrons in Canterbury gardens have been severely checked and some have been killed by this year's dry weather, but if next spring is kind the survivors will give a reward for persistence in the form of a copious display of flowering. Rhododendrons complete the major part of the process leading to the next season’s flowering between spring and midsummer, and plants which were irrigated well during the earlier part of the past summer have responded in many gardens by setting an enormous number of flower buds. Whether the shrubs will be able to carry these buds to maturity, or will shed them in a major bud-drop sometime after midwinter, will depend in large measure on the weather and temperatures over the next six weeks, and many growers will be keeping their fingers crossed.

I am among them, because several rhododendrons which have survived the drought in my garden have set buds for the first time.

Among these are the deciduous azalea species. Rhododendron schlippenbachii, and the officially evergreen Rh. yunnanense. The latter species is, like the great majority of rhododendrons, evergreen in most parts of New Zealand,, but when the weather gets really cold it has the ability to shed all its leaves without coming to any lasting harm; and its flower buds are reputedly very- hardy, unlike those of many popular hybrids, such as “Eldorado,” which drop off at a whiff of frost. Both the British and American Rhododendron Societies give . Rh. yunnanense i a four-star rating, but it is not seen often in New Zealand.

One reason for this may be its habit, which is to grow into a lax, willowy shrub usually 2m high but sometimes as high as 4m. It can be. a gawky customer in summer and autumn, but in spring it demands forgiveness when every one of its branches is tipped by large trusses of butterfly-shaped flowers. They may be white, lavender, or silvery pink, with darker spots on the upper lobes, and some have a contrasting burnt orange “eye.” When this plant is doing well and is well established it flowers so profusely that the leaves disappear from sight for a., fortnight. .. \. • There is something very distinctive about these deciduous rhododendrbns. There are several of them, but except among enthusiasts they are not well known. To most.gardeners, “deciduous rhododendron” means the Mollis azaleas which have been hybridised from Rh. molle, Rh.. lutpum) ,and othe azalea species Among;’ the, .non-azaleas are such treasures• as Rh. feuricum, an extraordinary plant which can' begin flowering in midwinter and can go on flowering in waves lihtil midspring. • t ■ Its buds are very frost-

resistant, so that if one crop of flowers is ruined, there is sure to be another coming on for the next mild spell. Rhododendron mucronulatum is another, a hardy bush with dense, twiggy growth profusely adorned with warm lavender flowers in late spring; my plant of this is less than 20cm high (it will grow eventually to 1.5 m) but flowered last year. In scale with the rock garden is Rh. lepidotum. which looks as if it should be evefygreen and has the peculiar habit of holding its frosted, dried-up old leaves throughout winter, tightly clasped around the flowerbuds. There are large and small forms of this species and as the smaller forms are har : dier they are the ones to look for. ' . My plant, several years old, is barely 15cm high and ; looks as if it will be able to< retain its niche in the rock,garden for some years tor come. ;• ■ . . ,? A winning characteristic of u; this species is that the -., flowers are held' above the foliage, open out ; flat, and even fold, back a little, so that the;.general effect is quite un-rhododen-dron like. The colours of the various forms range through

all shades from crimson to yellow.

My plant which came labelled “var. eleagnoides” (according to the best available references this is merely a synonym for the species), flowers in a curiously cool, orcreous yellow shade — what interior designers like to call “biscuit.” While these little rhododendrons in my garden have all. dropped their leaves as they usually do, one shrub which ought to have lost its leaves by now is hanging on grimly. This is the curious little Himalayan jasmine, Jasrninum parkeri. It is an odd man out in a. family mostly composed of climbers, because not only do its flowes have no scent whatsoever; it is a tiny, huddled shrub with no aspirations to height Most of the cultivated jasmines have been in gardens for centuries, but Jasminum parkeri is a relatively recent arrival, having been introduced only in the mid-19205. It was discovered in 1919 by R. N. Parker in the upper basin of the Ravi River in Himachal Pradesh, India, growing on rocks and hot, dry banks. In the wild it is apparently often reduced to dense, tennis ball-sized bundles of tightly packed twigs, but in cultivation it opens out and grows slowly into a rounded bush about 30cm high. It is a shrub that demands patience, because it is not easy to establish, and sometimes takes several years to settle down.. I found that it made no growth for a couple of seasons, and reacted to summer stress by shedding its leaves unseasonably; but now it has got its roots well down, and this year's drought left it unperturbed. The flowers appear in early midsummer, and are yellow, solitary, and large for the size of the plant, paler but otherwise not unlike those of the deciduous winter-flowering .'.species, Jasminum nudiflorum, which is just now coming 'into full bloom. The latter species is, of course, a climber and whereas J. parkeri is a sunlover J. nudiflorum thrives in, and perhaps prefers, shade.