Do we have class distinction in the garden?

Press, 15 May 1981, Page 10

Do we have class distinction in the garden?

ARDENER’S I DIARY

Derrick Rooney

May in the garden is the month of the reminder. Deciduous shrubs are dropping their leaves, perennials are dying back, and evergreen shrubs that have been overgrown all summer are poking their heads out again to reassert their status as the backbone of the garden. We are fortunate in this country that our flora is blessed — no, dominated — by some of the world’s finest evergreen shrubs. It can’t do any harm to be reminded of this every May, because apart from the flaxes, the cabbage trees, the kohuhus, the hebes, and a

handful of other workaday shrubs, the number of natives planted in gardens is very small.

Some of the real aristocrats of our flora are no more difficult to propagate and grow than the commoners, but they are ignored. I wonder why? Gardeners will go to great length to acquire new rhododendrons and camellias, but lose interest and quickly change the subject when you begin talking about a new olearia or a new pseudopanax. This is a pity, because while our native plants may in most cases lack the floral beauty of the rhododendrons, they have a beauty of form and leaf largely unsurpassed in other floras. And it is the leaves, not the flowers, that you look at for 11 months of the year. I suppose I am guilty, too, because the overwhelming majority of plants in my garden, even in the rock garden, are exotic; so I am adding some new native shrubs which, when they grow up a bit, will add an essential dash of chauvinism to the scene.

One of them belongs to a group which is among our most diverse and interesting families — the lancewoods. The common lancewood, Pseudopanax crassifolium, is one of New Zealand’s most distinctive hardy plants, both in its juvenile stage, when it is just a single stem with long, thin, fierce-looking brown leaves, and in adulthood when it is a small, mopheaded tree. ’ The lancewood is common in forests and scrublands throughout New Zealand, and comes up in gardens underneath bird-feeders — silvereyes are partial to its fruit. Pseudopanax lessonii, on the other hand, is a coastal plant restricted to the far north, with its southern limit in Poverty Bay. It is not hardy, at least not while young. P. lessonii actually looks more like the common fivefinger than a lancewood, because its thick, leathery leaves are divided into between three and five leaflets. Unlike the common lancewood, which very obviously

is a case of dimorphism, i.e. it exists in different juvenile and adult forms, the young P. lessonii looks very much like the adult, except that the juvenile leaves are larger than the adult ones. Both in the wild and in cultivation it has hybridised with other pseudopanax species, and the offspring of these illicit matings include a number of first-rate foliage shrubs. Several have been named, but mostly they are just sold as mixed hybrids — you takes your choice, and you pays your money.

Most of the named hybrids have as the second parent another far northern species, P. discolor, which looks even more like a five-finger. This lancewood reaches its southern limit on Coromandel but does go up to 900 m, so it is just hardy, though winter frosts in Christchurch sometimes singe its young shoots. I doubt if it would grow for me, and despite the tantalising charms of its selected clone, “Rangatira,” which does not grow very tall and has magnificently deep bronze foliage, I have resisted it so far — maybe next year. There are also hybrids with the common lancewood, and these are a more viable proposition in the colder areas; they will tolerate a lot of wind and drought, and frost, too, once they are out of napkins.

The mixed hybrids include many which are just as good as the named clones, and have the extra attraction of giving you something no-one else has. The seedling I picked out has spearheadshaped leaves as long as my open hand, glossy green and leathery, with little teeth on the margins and a consistent spattering of lime-green variegation along each side of the midrib.

It has obviously been grown in a shade-house, and the tip of the stem looks soft, so it will have to stay under cover on the terrace for a while with some other just-or-not-quite-hardy plants that are being acclimatised.

These include some exotics — the climbing Philadelphus mexicanus, which has the most elegant foliage among the “mock oranges” and lovely big, creamy, fragrant flowers in summer, but is definitely not hardy until it has made a good amount of hard, woody growth; Eucryphya cordifolia from Chile; and the “port wine magnolia,” Michelia figo, which has glossy evergreen leaves and smallish, fuscous flowers with an astonishing scent. There is a native in this infant’s room, too, a variegated form of one of our prettiest flowering shrubs, Olearia cheesmanii. The plain form of this shrub has been in my garden for a couple of years and can be

relied on in early summer for a fine show of white flowers. The variegated form is not common, and though I knew of it I had not bothered to seek it out because a book written by one of New Zealand’s leading horticulturists dismissed it in a couple of sentences as “unlikely to appeal to the discriminating gardener.” Now that I have seeh the plant I wonder whether he was looking at something else, or just having a bad day. It is an eye-catching shrub. The leaves are larger than those of the common form, and are lighter green, generously splashed, dotted, and striped with cream. Or perhaps it is the other way around. As it must have semishade to prevent sunburn on the cream areas of the leaves, it should be just the plant for a dull corner where I need something bold. No two leaves are the same and a well-grown bush is quite impressive among green and bronze foliage. My young bush will stay on the terrace probably until spring because it was grown in a Nelson nursery and its hardiness is in doubt. Another olearia that I acquired recently for its foliage alone is going to go straight into the garden as soon as possible, perhaps today if I finish writing this column in

time. I have no qualms about the hardiness of O. lacunosa, a tree daisy which occurs in scattered localities in both mountain and lowland bush from the Tararuas down to about Arthur’s Pass. ;; This is hardly ever seen in gardens, though it is one of our most handsome shrubs, remarkable for the long, narrow leaves, which give it the look of a lancewood rather than a daisy. “Lacunosa” means perforated or covered with tiny indentations, and I have to admit that I am baffled by its application to this shrub. The leaves are up to 17cm : long and as thin as a rake, with little teeth on the edge like lancewood leaves and a . prominent yellow midrib; they are rich green on the upper side and coated with brownish fuzz underneath. The flowers are insignificant. O. lacunosa in the wild is restricted to areas of higher rainfall than the Canterbury plains, but I believe that once established it Will, like the native “mountain holly,” O. illicifolia, tolerate quite a lot of drought. The latter has long, narrow leaves, too, but with sharp teeth and crinkled margins like a holly bush. It can be a slow starter (my bush sulked and refused to expand at all for a couple of - years), but once it gets its feet down it pushes up quite rapidly. Like most of the j olearias it is evergreen and, | once it has a bit of size, 1 • displays attractive, peeling j bark. , -• Both of these olearias, I | think, should be planted | more often, particularly the | mountain holly, because it is * very hardy and will grow in < the dim, draughty corners where garden design frequently falls flat.