Foliage for Effect in the Flower Garden

New Zealand Journal of Agriculture, Volume 101, Issue 4, 15 October 1960, Page 415

Foliage for Effect in the Flower Garden

By

J. P. SALINGER,

Horticultural Advisory Officer (Ornamentals), Department of Agriculture, Wellington

GARDENERS usually depend on flowers or berries to provide colour in the garden, but foliage either individually or in the mass can be equally effective and even more permanent and is especially important in winter in those areas where cold weather precludes the use of striking flowering plants. Many plants, of course, are colourful, both in flower and foliage, and these can be doubly useful, but even the foliage plants themselves can produce a most attractive effect; in fact this feature should be used more frequently in the garden.

WHEN buying plants, gardeners usually judge them for their beauty of flower, but they should also consider their overall effectthe general shape of the plants, the density of growth, and the reflective or absorptive power of the leaves. Though both camellias and roses are beautiful in flower, their general effect is quite different, a camellia normally having a dense, solid growth with dark but reflective leaves, while roses are judged almost entirely on their beauty of flower and occasionally on their fruits, the hips. One seldom admires a rose for its beauty of form as an individual plant. Growth can be either dense and compact or loose and spreading, rhododendrons on the one hand giving an impression of density while azaleas provide a much lighter effect. Leaf texture also is an important feature; it can be dark with a matt surface in contrast to polished green leaves or coloured leaves with a reflective surface. Apart from plants with green foliage, and the green can be anything from a very 'dark almost black green to a brilliant yellow green, plants can be obtained with leaves of many other colours —bronze, purple, yellow, gold, silver grey, and almost white. In addition many plants have variegated leaves, which are basically green but have coloured margins or marks on them. Some plants

also may have brilliant colours in their young growths, and, of course, there is always the beauty of the autumn colours of deciduous trees or shrubs. In fact many horticultural varieties of ordinary plants have been selected because of this variation in leaf colour, for instance, the variegated ivy, golden elm, and bronze flax. Use of Coloured-leaved Plants A most effective garden can be made with colouredleaved plants only, but generally they should be used with discretion either to provide a foil for other plants or to accent an area, especially in winter. Plants of a subdued dark green or brownish colour provide a background to more vivid colours, while those with gold, silver, or purple leaves can be used for accent. Grey foliage dwarf plants provide an attractive border both to bright- and pastel-coloured flowers. Occasionally a coloured hedge will provide an interesting contrast to most gxeen-leaved hedges. There are several plants for this purpose: Abelia Photinia glabra rubens, golden lonicera and privet, purple ake ake, and variegated box. Plants with grey leaves are generally resistant to wind and salt spray damage, as the colour of their leaves is formed from minute hairs or scales. These plants are particularly suitable for coastal areas and provide a contrast to the other type of wind-resistant plants—with hard, glossy green leaves. Coloured-leaved plants are particularly attractive when blended on the margins of pools and streams. The water will reflect both their colour and shape. Along larger areas of water, willows of various species are

particularly suitable, and near small pools dwarf bamboo, ferns, and hostas are suitable. In the rock garden the dwarf conifers are very useful for their foliage and shape, but many of the dwarf alpine plants can be used for the same purpose; saxifrages and primulas, the native celmisias, and pachystegia are all attractive. On steeper rocky banks more vigorous plants like arctotis, bugle, and the variegated forms of tradescantia and ivy will provide a colourful ground cover. Among coloured-foliaged trees and shrubs the many variegated forms of popular conifers are especially useful. Some of the tree species of these are attractive themselves because of their shape and growth habit, such as the deodar cedar and Spanish fir. The few deciduous conifers are attractive in. spring as the young growths develop and again in autumn before the leaves fall. These conifers are larch, swamp cypress, and dawn redwood. There are many attractive variegated forms of the evergreen conifers, especially of Lawson’s cypress, Japanese cedar, junipers, and yew. They grow in upright or spreading forms, but some are quite dwarf and suitable for the rock garden. These plants are generally less resistant to the wind than the normal form and so should be given some protection to

develop their true habit and full colour. Evergreen Trees and Shrubs A few evergreen trees in their natural growth provide a distinct colour; Magnolia grandiflora, for instance, has a brownish underside to the leaves, and holly and camellia

varieties , frequently have variegated leaves. There is no doubt, however, that New Zealand native trees and shrubs, though not outstanding for flowers, are most effective in foliage; overseas, plants such as black matipo are cultivated commercially for this purpose. The wide range of colour that can be obtained in native plants is shown by the large green leaves of puka, the yellow green of young rimu, the variety of greens in Pittosporums, the grey of senecios and some olearias, and purple ake ake; in addition there are garden varieties of many natives such as variegated lacebarks and the variegated parapara. New Zealand natives

provide an alternative to many conifers and could certainly be used much more than they are, purely for foliage effect. Some South African plants on the other hand, are beautiful for their silver or grey foliage; they include

Cape silver tree, satin bush, and Leucospermum species. Deciduous Trees and Shrubs Deciduous trees and shrubs can provide much beauty, especially in spring and autumn. A few species have coloured leaves and are attractive all through summer; they include maples, purple-leaved plum, claret ash, and golden elm, while there are variegated forms of abutilon, diervilla, bamboos, and dwarf heaths. Herbaceous and Bedding Plants In addition to trees' and shrubs many bedding plants are effective for their foliage colour; they include alternanthera, irisine, fibrous begonia, and burning bush. Variegated forms of geranium are frequently used for bedding and these coloured-leaved plants generally can be used for group effect by themselves or to blend with more brightly coloured flowers. In formal bedding schemes large plants such as the purple castor oil plant or variegated abutilon are used as individual specimens, while at other, times dwarf plants like variegated arabis or golden feather are used as edging plants. Herbaceous plants are usually grown for their beauty of flowers, but a few also have attractive foliage. In particular there are variegated hostas and the purple-leaved , Lobelia cardinalis; the various dusty millers provide a grey or silver foliage which can be most effective. Their very name indicates their foliage. Even the vegetable garden can provide coloured varieties of popular vegetables and herbs and these are frequently grown for both ornamental and culinary use. There are colouredleaved kales, willow-leaved beet, and coloured-stemmed silver beet, and among herbs there are many colouredleaved forms of thyme and sage.

Work for November

By

JOY WATKINS,

Horticultural Advisory Officer, Department of Agriculture, Auckland

New Zealand gardens are probably at their loveliest in November. It is the month of roses, not only the modern varieties but also the old fashioned shrub roses. Their beauty may be fleeting, but a garden of these old types is a sight, and scent, to remember.

Few people can resist the charm of Cecile Brunner, which is rarely without a flower and flourishes in most gardens; and there are other equally attractive varieties, most of which are

now stocked by specialist nurserymen. Most old fashioned shrub roses should be pruned immediately after flowering, as much as possible of the old wood being removed to allow* the young stems to grow and ripen well. Those who intend planting up more roses in their gardens would be well advised to visit shows this month. The individual flowers are more easily compared on the show bench and there is usually a good display of the standard and newer varieties. This first selection should be followed up with a visit to the nursery in February, when the plants will be in full flower, so that the vigour and habit of the varieties and therefore their garden merit can be judged. Flower Shows Most flower shows are held throughout the country this month and a gardener usually learns a little from each. Those who plan to exhibit for the first time can learn much from studying the prizewinning exhibits in any of the larger shows. They will realise the standard that is expected and the faults to avoid in the selection or staging of the blooms. So much depends on the selection of blooms; an even collection of high quality must be picked at the right stage and then given the right treatment so that the blooms are at the peak of their perfection when the judge sees them. Most blooms should be picked 24 hours or more before and stood in deep, cold water in a cool, dark place until they are taken to the show. Picking before they are

mature will cause some flowers to droop. If blooms are left too long on the plant, the pollen is shed and they begin to age. Making some experimental pickings before the show is worth while to discover the best stage at which to pick them. Judging Points In the selection of flowers the following points should be remembered, as they are the ones on which the flowers will be judged: Stems should be straight, firm, and strong enough to carry .the bloom at the correct angle. Foliage should be healthy and unblemished, ■’ any spray deposit having been sponged off. The flower should be well shaped, with firm, unblemished petals of good quality and texture and even or well marked colouring. Florets in the centre of a daisy-type flower should be young and preferably without pollen showing. Spikes should be straight and evenly tapering, with as many flowers open as possible without the oldest flowers fading or having been removed. The flowers on a spike should be evenly spaced without gaps or overcrowding. Naturally there are finer details to be considered for each flower, but these can be learnt only by studying the best specimens of that flower and by getting advice from specialist growers. Carnations Carnations and gerberas are a feature of most New Zealand gardens and some home gardeners are hybridising and raising new varieties. Many more save seed and take a chance on

the parentage, so that the resulting seedlings are a “lucky dip”. Seed should be sown as soon as it is ripe, as it rapidly loses its power of germinating. Vigorous stocks of the lovely old carnation variety Otaki Pink are becoming rare and growers looking for another variety to replace it as a cut flower during summer might like to try Pink Perfection, which has large flowers and long, strong stems, but little scent. Rose Clove is still one of the best winter flowering carnations. The newer Sim varieties are being tried here, but generally they are not a success unless grown in a glasshouse. Snails can cause considerable damage to all carnations and pinks, and bait should be put down regularly. Shrubs Shrubs should be growing well. Any which are healthy but not growing vigorously can be given a little blood and bone. It is better to make two or three light applications during summer than one heavy application. Shrubs which, though growing well, persistently refuse to flower can be given a light dressing (about 1 oz to the square yard) of sulphate of potash. The possibility that they are growing in the wrong positionwith insufficient exposure to sunshine, for example should also be considered. Incorrect pruning, by consistently removing the flowering wood, can also prevent a shrub from flowering. Fertiliser should not be applied to South African and Australian shrubs, as most of these grow and flower best on the poorest of soils as long as they are well drained. Shrubs which tend to produce very long, straggly stems, such as poinsettia, luculia, fuchsia, and lassiandra (Tibouchina), may be tipped to promote compact growth. Only the tips of the shoots should be pinched out. Some of the newer varieties of poinsettia are much more compact in habit, though few are yet available in New Zealand. Poinsettias are grossfeeding plants and the biggest “flowers” are grown on well fed bushes. Rotted cow or poultry manure can be used. Shrubs and trees which were planted last winter must be watered as necessary and mulched. Shading with paper or scrim is beneficial if a small shrub tends to wilt during the day. Photinia hedges should be clipped early in November to look their best for Christmas, as it takes about six weeks from cutting for the new shoots to develop their young red leaves. Late spring-flowering shrubs, such as forsythia, can be pruned as soon as they finish flowering, the oldest branches being removed entirely or cut back to younger side branches growing near the base of the shrub.

Podalyria calyptrate may be pruned back hard after flowering, though old bushes which have not had this treatment regularly should be treated more gently. Fuchsias root readily from cuttings only 2 or 3 in. long taken from the tips of young shoots. They will root in water or in a light, sandy soil mixture. Keep them shaded until they are rooted and grow them on in a bush house if one is available. Continue replacing late spring bedding plants. Water the plants well after planting and if possible transplant them in the evening. Temporary shading where practicable will also help them to become established. If plants have been raised in the home garden, water them well the evening before transplanting. Sowing Herbaceous Perennials In warm, sheltered gardens the first sowings can now be made of biennials and perennials, many of which will flower toward the end of the first season. The ground should be well prepared beforehand, and a little bone meal worked in, as this encourages the growth of seedling roots. The place chosen for the seedbed should be as free as possible from weeds, as some perennials are very slow to germinate and can easily be smothered by strong growth of weeds. Any weeds which germinate should be removed as soon as recognised, as removal later will disturb the flower seedlings too much. If perlite or similar material is used to cover the seeds, it will be easier to see the tiny seedlings in the rows. Seeds are frequently sown too thickly and too deeply. Small seeds

can be mixed with sand, perlite, or dry soil before they are sown, then covered with their own depth of the same material. Water them in with a fine spray and continue watering and shading as necessary until the seedlings are well established. Hard-coated seeds such as lupin can be soaked in warm water for a few hours to soften the seed coats and accelerate germination; or they can be nicked with a knife to allow water to enter. Some lilies flower during the first season when seed is sown in October and November, but others take two or more years. Home gardeners can raise many species and hybrids in this way at a much more reasonable cost than buying the mature bulbs. Seedlings are normally free of the mosaic virus disease, so that it is a way of producing healthy offspring from diseased plants, which should be destroyed. The seedlings may not be identical with the seed parent plant, but the variation may be just as attractive for decorative purposes in the home garden. The lilies should be left in the nursery bed until they have flowered. Any very poor types can then be destroyed and the remainder moved to their permanent position in the shrub or flower border. Iris innominate can now be divided, though autumn is perhaps a better time where the soil and other conditions are suitable. Division must be done very carefully to avoid losses, as this species has a poor root system. One year old plants are preferable to old clumps.

If an old clump has 'to be divided, only the young actively growing outside portions should be retained and the mass of old rhizomes'in the centre should be destroyed. Lift clumps with a large mass of soil so that all the roots within 6 in. of the clump all round are undamaged. Shake or hose off the soil and pull the clump apart with the hands; never use a spade to divide this iris. - Clumps should not be reduced to single pieces of rhizome, but left as three to five pieces of attached rhizome in each division. The divisions should be replanted at once, as they die if they are allowed to dry out. If many clumps are being divided, place the divisions under a damp sack until ready for planting. Plant in fresh soil if possible; otherwise when the bed is being prepared water the soil with copper oxychloride (1 lb in 10 gallons of water to 5 sq. yd) to reduce the risk of soil-borne diseases. , Established plants can be watered with this solution about once a month during the growing season. Plant in a semi-shaded position in soil well enriched with leaf mould or compost. Iris innominata can also be raised from seed sown this month, and this is a good method of producing a number of plants with flowers of different colours.

Pests and Diseases Pests and diseases are numerous this month on the soft young growth. Roses are subject to rust and mildew, for which a spray of 3g fl oz of lime sulphur plus g oz of colloidal sulphur in 4 gallons of water is required. Powdery mildew is always worse if the plant becomes dry .at the roots, so watering and mulching are beneficial. Brown and bronze beetles are common, eating holes in flower buds and the leaf edges of roses and a variety of other plants. A weekly application of j- oz of DDT 50 per cent wettable powder in 4 gallons of water should be given. DDT can be added to the lime sulphur spray referred to above. Caterpillars and weevils will also be controlled by the DDT spray. Aphids multiply rapidly, and should be dealt with as soon as' noticed. Soapy water is a mild deterrent, but there are many more effective controls, such as lindane, malathion, wettable powder, and nicotine sulphate, all of which should be used at the weakest dilution recommended by the manufacturers. Red spider and thrips are hotweather pests of many plants. Malathion emulsion at 1 fl oz in 4 gallons of water controls both.

Spraying with clear or soapy water will also discourage them, as they dislike a damp atmosphere. Eucalyptus tortoise beetle is becoming more common in the North Island and has been found on a variety of plants. It looks like a tiny tortoise, about i in. in diameter and varying in colour from sandy grey to orangered. It eats gum leaves and possibly those of other plants. Bulb flies are on the wing, laying their eggs in the holes left by the dying leaves of narcissus, hyacinth, amaryllis, and iris. Hoeing and drawing the soil up over the bulbs will help to protect them. Dusting with DDT or drenching the rows or groups of bulbs with 1 oz of 50 per cent DDT wettable powder in 6 gallons of water in early December and again two weeks later is a more positive control. House Plants These should be growing rapidly, so they can be watered 1 more frequently and given a liquid feed of a . proprietary foliar fertiliser about once a fortnight, particularly if pot bound. Protect them from strong sunlight and do not splash the leaves when watering, as this can cause the development of brown scorched areas in the leaf, particularly toward the tip.

Apart from being unsightly, such damage can allow the entry of grey mould and other diseases. Propagation of house plants by leaf or stem cuttings or division can continue. Pot plants for exhibition at shows should appear robust and healthy with clean, undamaged foliage preferably covering the top of the pot. Foliage which is scorched or distorted is undesirable, but evidence of removal of damaged leaves. will also be a disadvantage. Growth should be even all round. Flowering plants are generally considered slightly superior to nonflowering types in open competition, as more cultural skill is usually required to bring them to the fullflowering stage for the date of the show. The flowers should be numerous, evenly distributed, and held well above the leaves so that they are easily seen. The individual flowers on the plant should be of good quality and texture, well formed, and with a good, bright colour. Hanging Baskets Home gardeners may like to have hanging baskets to decorate their verandas, bush houses, or glasshouses, but problems of planting and watering have to be overcome if the baskets are to look really attractive. The container is of galvanised wire and this should first be lined with a sheet of clear plastic, a few holes being made for drainage at the bottom. Closely packed moss was formerly used, as it held the moisture and prevented the soil from trickling through the wire mesh. It can still be used in a thin layer to line the plastic, giving a more attractive finish to the basket when viewed from below. Pot-grown plants are the easiest to transplant into a basket and several can be packed in if they are in small (2J in. to 3 J in.) pots. The central plant is placed upright with the others spaced out round it at an angle. A good potting mixture is placed in the bottom and firmed down, then the plants are knocked out of their pots, crocks removed, and bottom roots loosened a little before the plants are placed in the basket. More potting soil is then firmed down round the root balls until the basket is filled to within an inch of the rim. The new soil should be as firm as that in the root ball; otherwise the latter will not be wetted when the whole is watered. Care should be taken that the plants are kept in the same level in the soil as that in which they were formerly growing. The surface. of the soil should dip slightly in the centre and the moss and plastic should continue to the rim of the basket to facilitate thorough watering. If potted plants are not available, suitable plants can be lifted with a good ball of soil from the open ground and planted in the same way as above.

If seedlings or rooted cuttings are used, the basket should be filled with potting mixture, and the plants put into it in the same way as when they are planted out in the garden. The basket is usually handled more easily if it is supported in the top of a large flower pot, can, or box during planting. Suitable plants are those with a naturally lax or pendulous habit, such as fuchsia, trailing lobelia and petunia, ivy-leaved geranium, some begonias, Asparagus sprengeri, Panicum variegatum, chlorophytum, ferns, wandering jew, heliotrope, Campanula iso'phylla, and Saxifraga sarmentosa. They should be chosen according to the position they are to occupy, those which appreciate a shady moist atmosphere being used for the bush house and those which can stand hot sunshine and dry conditions for the veranda. Watering should be done regularly, possibly every day in midsummer. If the soil becomes very dry, the whole basket should be placed in a tub of water for an hour or two and then the surplus water allowed to drain away. Baskets lined with plastic do not need such frequent watering as those made up in the traditional manner. As for pot plants, the soil should be kept neither sodden nor dry, but just damp. Water with one of the proprietary foliage feeds once every two weeks throughout summer to maintain vigorous growth. The baskets should be hung above head height if they are over a pathway, but they should be easily accessible for watering and spraying. This can be arranged by hanging the basket by a rope which passes over a pulley to a hook on the wall. Bulbs, particularly lachenalias, can look very attractive in baskets. The basket is first lined with moss, then the bulbs are placed fairly close together facing toward the outside of the sides and bottom of the basket. Fill the basket with potting soil, placing a 5 in. pot in the top, cover with a board or tile, and turn the basket upside down. At the same time plant five bulbs in a 5 in. pot and grow them alongside the basket. When the bulbs are in bud, invert and hang the basket and replace the empty 5 in. pot with the one full of bulbs. Within a few days the basket will have the appearance of a globe of flowers. Floral Decoration Gerberas should not be picked until that part of the stem immediately below the flower is firm, that is, about two days after the flower is apparently fully developed; otherwise the head will droop. Roses last longer if they are picked in the late afternoon, with one or two petals unfurled from the bud. Slit the stem and scrape the bark for about an inch from the base with a sharp

knife, and place immediately in cold water so that the whole stem is immersed. If there is any delay between cutting and placing in water, recut the stem under water, removing about half an inch. Leave in a cool place overnight. This may seem rather a lot of trouble, but it. ensures that the roses will last for a reasonable time. After being arranged they should be placed in as cool a place as possible, out of the sun and out of draughts. Single specimen blooms of a new or favourite variety look well in the small silver or crystal vases designed for the purpose. With such a wealth of flowers available, it is a good time to experiment with all types of flowers and foliage, mixing and blending colours and trying various styles of arrangement which may be unfamiliar. If the flowers themselves do not suggest sufficient ideas, guidance can be obtained from illustrated books from libraries and bookshops.

1 f Book Review | a Llzmjiiiii H h 1 H LP

“The History of the Loder Cup”

T»HE Loder Cup, named after its A donor, Mr Gerald W. Loder (later Lord Wakehurst), is in the terms of the award “offered to lovers of nature in New Zealand to encourage the protection and cultivation of the incomparable flora of the Dominion”. The award of the cup is vested in the Minister of Agriculture, who appoints the Loder Cup Committee to assist him in selecting suitable recipients. The award of this cup is highly regarded, and many persons noted for their activities in the preservation or the development of interest in native flora have won it. The Loder Cup Committee has now published this attractive history of the first 25 years’ awards. This well illustrated book is a worthy record of the recipients and of the many other persons associated with the award. It is most valuable in providing a factual history before the information becomes forgotten or distorted by time, and it should encourage many others to work for the objects of the donor.

—J.P.S.

Published by the Loder Cup Committee; obtainable from the Royal New Zealand Institute of Horticulture (Inc.), P.O. Box 450, Wellington. ss.