We seem to have come a long way with indoor plants in the last quarter of a century as plants in an ever-increasing variety are produced in their millions annually for an eager and interested public.

Often I am asked whether I foresee any falloff in demand, but my optimism is as boundless as ever. The more houses that are built, the more mammoth office blocks that appear on the horizon, then the greater will be the potential for decorative indoor plants.

Wherever you hear of the green-fingered ability of someone who grows all the plants in the hook with consummate case it will often he fitund that they invariably provide almost ideal roots as soon as the cutting is pointed at the compost.

The general paraphernalia connected with plant culture indoors has kept step with increased world sales of plants. We now have an incredible assortment of simple and sophisticated, expensive and less expensive containers to choose from in which to accommodate our plants.

Since then we have raised many delicate plants equally well by using the same material for plunging pots. Filled with moss instead of peat or compost, containers are much lighter and easier to handle, and there is little chance of the moss becoming, excessively wet. Indoors, containers some 15 in. in diameter and about 5 in. in depth can he filled with moss and a collection of five or six plants used to give a very pleasing effect.

Besides selecting good quality plants and creating humidity, it is also necessary to provide light, airy and reasonably warm conditions. A temperature in the region of 16 to 18C. (60 to 65F.) is adequate for all but the more tender tropical types of plant. Excessive heat can often present more problems than temperatures that are slightly below ideal requirements, especially if the atmosphere is very dry. Excess in most things is detrimental, and it would certainly seem to apply to plants where moderation does, on the whole, give much better results.

Spiraeas have filled so many ugly gaps for me that it would be easy to take them for granted were they not such attractive shrubs. Most species have a graceful arching branching system, dainty foliage, and white flowers, except in the species Spiraea x bumalda.

Foam of May, S. x arguta, looks like a shrubby maidenhair fern with cascades of white flowers in May on bushes 4 ft. high. S. x bumalda Anthony Waterer astonished me last year by producing cream- coloured leaves on one bush, but apparently this is not uncommon. The crimson flowers are borne on stiff upright 3-ft. high stems and are a little too prim and precise for my taste.

Of this genus none can rival our native Rowan or Mountain Ash. Even when grown in some suburban gardens the deeply divided leaves and orange-scarlet berries hint of the wide reaches of moor and lonely upland loch. First, in alphabetical order must come the whitebeam, Sorhus aria, with leaves which are green on the upper surface and silver grey underneath. The fruits in autumn are highly coloured and irresistible so far as the birds are concerned.

The species H. paniculata grandiflora makes a very impressive sight in late summer, especially when the shoots are thinned to allow full development. The branches arch over with the weight of the panicles which open first to white then fade to pale pink. H. villosa is one of the loveliest of the late summer-flowering species with large lilac-blue inflorescences.

Internodal cuttings of side shoots will root in sandy compost with most varieties. With paniculata, however, layering of the previous year’s growth offers the more reliable increase.

Hydrangea macrophylla covers a large and varied group of hydrangeas, many of which are of possible hybrid origin, and may be divided into two groups, namely the hortensias and lacecaps. With all the florets sterile the hortensia group develop positive football heads of flower, the blueness of which depends on the acidity of the soil. This can be induced by applying aluminium sulphate or generous dressings of peat.

Just as good-natured people are usually called upon for all the arduous chores, so do we tend to take advantage of plants like hypericum which will grow in the least salubrious corner of the garden.

Like the lavender, rosemary is loved for its old world charm, and aromatic foliage. In all but the wettest soils the height is about 5 ft. and it endures clipping sufficiently to make a hedge, as I have done utilising plants grown from cuttings of semi-ripened wood. The blue flowers open in my garden in June and the bush has been planted around with glaucous-leaved, pink-flowered dianthus so both the colour and scent can mingle.

Fruhlingsmorgen and Fruhlingsgold grow to a similar height, 6 to 8 ft., and are alike in leaf and smell, but the one has cherry-red flowers centred yellow, and the other petals of palest primrose.

I grow all the forms of R. moyesii available and when named varieties are exhausted I experiment by growing more from seed. R. moyesii Geranium is more compact than most with the typical delicate leaves, orange-scarlet flowers, and flask-shaped hips, while Sealing Wax has red flowers followed by orange hips backed by the soft yellow dying leaves. Nevada with white blooms and the bud sport Marguerite Hilling with pink- should also be included here for both have R. moyesii as parent. R. xanthina Canary Bird has the beauty of finely divided leaves with small canary yellow flowers in June, followed by vivid red hips.

Alders are often planted near water or in moist areas, but their ornamental attributes are often overlooked. Even the native forms, have interest. The cut- or golden-stemmed forms acid variety and interest, making them worth planting provided they are in the right type of soil. The soil is acid or alkaline. but prefers moist soil; dislikes very dry conditions

It requires moisture-retentive soil high in organic material Aspect Full sun to light shade. It forms a neat, small. round-topped tree. Its leaves are deciduous, grey-green to mid-green, excellent display of orange, yellow and bronze autumn colours; hand-shaped, 5-10cm (2-4in) long and wide, with toothed edges. It has short, pendent racemes of green to yellow-green flowers in spring.

The other species I treasure under the shade of a Malus x purpurea is W. middendorffiana. This bush at 4 ft. high is a wonderfully delicate picture when covered with pale yellow flowers, each blotched with orange in the throat. So popular are the weigelas that quite naturally there has been a vast amount of cross breeding with a resulting plethora of hybrids.

All do well with a cool moist root run and shelter from late frosts and the east wind. I love to see them in open glades interspersed with the pale green and white of silver birch.

Among the varietal forms of the hybrid R. x loderi are the cream of the rhododendrons, both species or hybrids. I have seen them 15 ft. high so covered in pink flowers that the colour filled the garden. My bushes after 15 years are only half that height but in flower and foliage magnificent.

Mrs G. W. Leak is so utterly reliable that no frost has yet marred the array of pink flowers, each with a purple blotch at the throat. To this must be added the ability to resist the most vicious east wind. I use Pink Pearl with restraint. It is strong growing and with a rather loud rose-pink colour needs careful handling.

A silver spruce makes a suitably subdued background. Purple Splendour flowers in June and would be worth a place for the copper colour of the young growths. The deep purple flowers are not everyone’s taste and the loose and spreading habit of the branches takes up room but it looks delightful when under planted with meconopsis.

Cotoneaster microphyllus thymifolius is hard, ground hugging and rather like wire netting with leaves on. Planted in the rock garden it will follow and emphasise every rock and contour in a splendidly affectionate way.

Cotoneaster nitens is especially desirable for the beauty of the leaf colour in autumn, particularly when planted around with Lilium speciosum.

The Common or Scots Broom, C. scoparius, which makes a golden glory of the sheltered valleys in Teesdale has given rise to many hybrids. Cornish Cream grows up to 8 ft. tall with pale yellow flowers in July and together with Darley Dale in crimson and yellow, Firefly in crimson bronze, and Red Sentinel in deep red, it is worth a place in any garden. Cuttings of semi-ripened shoots taken in July – August, 3 to 4 in. long with a heel of old wood, root readily in sharp sand. Make certain the soft pith is not exposed or an imperfect callous forms.

Daphnes are invaluable shrubs for both border and rock garden. A loam soil, enriched with humus yet well drained is all my plants ask for and this I give freely for the privilege of enjoying their delicately perfumed flowers.

I grow amelanchiers from seed because not even in a mist unit will they condescend to root from cuttings with any degree of certainty. Amelanchier canadensis, the Shad Bush, comes very high on my list of indispensable shrubs. Even in winter the graceful form of the plant is obvious.

Autumn, though in glorious beauty my favourite season, is but a fleeting moment in time, so I prefer in a limited space to grow A. palmatum atropurpureum, with finely divided, bronze-purple leaves which delight me from bud burst until leaf fall. The acme of maple perfection is, undoubtedly, the finely divided leaves of A. palmaturn disseetumatro purpureum which I grow surrounded by ferns and meconopsis. The setting sun will shine through the tree to turn the purple leaves to rich wine red.

Amelanchier x grandiflora is a hybrid with canadensis as one parent. I prefer the pink- flowered form listed by some nurseries as rubescens, by others as rosea. Pink candyfloss would be an exact description of this bush in full bloom, the autumn colour of the leaves being a rich deep red.

Berberis dictyophylla came to me as a chance seedling in a box of mixed shrubs. The plant is now 4 ft. high, the young shoots scarlet but covered with a grey bloom.

In the autumn the leaves are absolutely delightful, first green rimmed scarlet which deepens until the whole leaf is bright silver and red.

B. x irwinii will always be represented in person in my garden, or by one of its numerous offspring, for they rank with the choicest shrubs. The type is a dwarf bush, 3 ft. high, with arching branches. The flowers, which are crimson in bud and orange- yellow when they open, appear in April.

Finally, having ignored the vast legions of berberis worthy of notice but not of the elect, to B. wilsoniae, a dwarf shrublet only 2 to 3 ft. high. The tiny grey-green leaves in autumn turn deep red, as if to vie with the orange-scarlet of the fruit. Judging by the way the rabbits haunt this impenetrable tangle of branches I have often wondered if this is the original thorn bush Brer Fox pitched Brer Rabbit into.