Growing methods

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The following is a selection ot flowering and foliage plants commonly grown in the greenhouse by amateur gardeners. There arc, of course, hundreds of such plants suitable tor growing under glass or plastic, but space allows us to deal with only a few. The selection is, however, varied enough to plan a range of alternative programmes, including mixed cropping with food plants (str Chapter 6),

Each pot plant should be regularly examined for signs ul posts and diseases

Each pot plant should be regularly examined for signs ul posts and diseases

Biodome GreenhouseAsparagus Ornamental Plumosus Nanus Pics

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I Asparagus Ferns

Suitable tor growing in the cool green-bouse, the asparagus ferns are half-hardy perennials renowned tor their attractive foliage. A. plumosus nanus has slender, delicate foliage much used by florists as a background tor buttonhole flowers; the dark green needle-like _ foliage of A sprcnyeri, with its pendu-1 lotis habit, is liked both by flower arrangers and by hanging-basket enthusiasts.

Asparagus ferns are normally grown in pots in John lnnes Potting Compost No. 3 (JIP3} or in a soil-less compost. Frequency of feeding during the summer growing season will depend to some extent on whether the foliage is being cut or the plants are allowed to grow without disturbance. In the former case use a general fertilizer with a high nitrogen content. As the plants grow in size, pot on into 130 mm (5 in) pots. For propagation, the plants may be divided 111 March or, alternatively, raised from seed in early spring in temperatures of around 10 C (fix F),

40 flowering and foliage plants

Bamboo Asexual Propogated Methoda

The lovely Camellia 'Waltz Time'

Camellias

Although camellias grow satisfactorily out of doors in southern parts ot England, they develop the finest blooms when grown in the greenhouse. They need little or no applied heat, and if suitable varieties are selected they will provide beautiful pink, red, or white flowers from October through to April. When the young rooted plants are received they may be potted straight into i .10 mm (> in) clay pots using a lime-free compost; if you prepare your own John Innes formulation, omit the chalk. If a loamless compost is used, ensure that it is of a type suitable for acid-loving plants.

file plants are normally grown out of doors from the late spring through to early autumn; it is best to plunge them m their pots in an ash bed. If this is done they w ill require regular watering. but the risk of their drying out (which can cause buds to drop off many months later) will be reduced. Being evergreen the leaves will get dirty unless syringed regularly, and soft water should be used tor this; 111 hard-water districts use rainwater both tor syringing and tor normal watering.

When camellias have finished flowering they should be lightly pruned to maintain their shape. Pot on when necessary.

The lovely Camellia 'Waltz Time'

Popular border carnation Alice Forbes

Carnation Alice Forbes

Car iiiit ions

The perpetual-flowering Dianthiii varieties are hardy and will grow well with the minimum of heat, giving blooms for most of the year. Carnations prefer .1 cool, airy greenhouse which is why chose who exhibit them regularly grow them on their own. Well-grown plants will reach a height of more than 2 m (6 ft) and so must usually be grown in a greenhouse with glass right down to the ground.

It is best to buy young rooted plants early in the year, so that you start with clean, healthy stock. The nurseryman should have 'stopped' the plants (removed the growing tip) before despatching them to you, in order to encourage the side shoots to develop. On arrival they should be potted into yo mm {3 I in) pots. Later, before they become pot-bound, they w ill need pot ting on into 1K0 nun (7 in) pots, using JIP3 or a loamless compost. By this time the side shoots will probably be about 130 mm (5 in) long, and they in turn will need stopping by removal ot the growing tips, fhe side shoots grow at different rates, so stop the fastest-growing one first to prevent them all flowering at the same time.

From then on the plants will grow-steadily it regularly provided with a proprietary liquid feed. They need support from an early stage and four canes per pot will be required when they have been transferred to the tNo mm (7 in) pots; alternatively, you can use the neat purpose-made carnation supports sold by most sundriesnien.

Disbudding is necessary to get worthwhile flowers, so as soon as you can see that the terminal or crown bud is undamaged remove the buds that form immediately beneath it. Removal ot the flowering bloom with its stem is a form ot pruning, and it only remains to train in new growths. Perpetual-flowering varieties provide a continuous succession ot blooms for two years or more. It is then best to destroy the plants and start afresh.

Some types of carnations can be grown from seed sown in the propagating frame early in the year. As they grow they may be potted into small pots or widely spaced in boxes. If planted out in open ground in April May they will flower in August. In mid-September, it carefully lifted and placed in pots in the cool greenhouse, they will continue to provide colour throughout the winter months. Many ot the varieties are scented.

Popular border carnation Alice Forbes

Chrysanthemum Cultivation Greenhouse

Chrysanthemums grow in a cool greenhouse

Chrysanthemums

Chrysanthemums are likely to form the basis of many cropping programmes because they do not occupy the greenhouse for what can often be its busiest time, from May to nudSeptember. They rate highly asa valuc-for-moncy plant: they give a lot of colour over a long period, and they are relatively hardy and versatile. Depending on variety they may be grown simply as decorative plants in the borders, as short pot plants, or in pots for exhibition purposes. (The National Chrysanthemum Society classifies indoor varieties as Large Exhibition, with petals incurving and reflexing,

Medium Exhibition, Exhibition Incurved, Reflexed Decoratives, and Intermediate Decoratives.) Cool greenhouse temperatures are adequate for all types.

cultivation Most chrysanthemums arc propagated by means of cuttings and, when starting, the greenhouse gardener would be well advised to buy young rooted plants from a specialist raiser. In this way he is assured of getting healthy young plants, virus-free and true to type. If he looks after them properly he can propagate his own plants from these in future years.

On arrival in March or April the

Chrysanthemums grow in a cool greenhouse young plants are potted up into yo mm (3! in) pots using |llJi or a soil-less compost. They will need some warmth initially and space should be found on shelving where they will get a reasonable amount of direct sunlight. Unless they are being treated as lifted chrysanthemums, it will be necessary to pot on into 130 mm {5 in) pots before the plants get pot-bound; as they are vigorous growers, this stage may be reached in four to five weeks. If you arc using a loam-based compost it is usual to compress the soil rather more than one would normally do: 'pot firmly' is the

Potted Chrysanthemum

. Potted chrysanthemums 1 Rooted cutting in a 90 mm (3$ in) pot, 2 The break bud: 3 First crown buds. A Second crown buds 5 Pinching out a growing tip

. Potted chrysanthemums 1 Rooted cutting in a 90 mm (3$ in) pot, 2 The break bud: 3 First crown buds. A Second crown buds 5 Pinching out a growing tip advice often given to beginners. In the bigger pots the plants take up a substantial amount of room, so they should be moved to a cold frame as soon as they have settled down after potting on. They must not get frosted in the frame, so if a cold night is expected cover the plants with sheets of newspaper.

In June the plants are moved into stili larger pots t So or 220 mm (7 or 8^ in) - and stood out, 7.s to 100 mm (3 to 4 in) apart, on boards or slates. Here they remain until they are returned to the greenhouse 111 mid-September.

Many amateurs will prefer to adopt a less elaborate system. Lifted chrysanthemums, for instance, are quite suitable for decorative purposes. The plants, in 90 mm (3; in) pots, are moved to the cold frame to harden off. In May they are planted 380111111 (is in) apart in well-prepared ground out of doors. Here they remain until mid-September, when they are lifted with care from their summer quarters and transferred with as much soil as possible into the greenhouse border. I like to prepare the plants for this move by driving in the blade of a spade to its full depth around halt the plant, and some

130 mm (5 in) from it. five weeks before lifting, a fortnight later repeating this around the other half of the plant.

Left alone, a young chrysanthemum plant with one or more pairs of leaves will develop a bud at its apex which will not form a flower; this is known as a break bud. From the axils of the leaves below this bud, young shoots will appear - a phenomenon known as a 'natural break1. The buds that form are called first crown buds, They may abort in turn and the process will be repeated, with the flowers forming on the next lot of buds; these are called second crown buds. The timing of flowering and the number and size of blooms are affected by this process, In practice, some manipulation by pinching out is usually necessary and a good chrysanthemum catalogue will make recommendations tor each variety.

As a rule the greenhouse decorative varieties carry their flowers on second crown buds. The gardener does not wait for the break bud to form but pinches out the growing tip ot the plant while it is still in its first pot and is t 50 to 230 mm (6 to (J ill) tall. When these growths are about 250 mm (10 in) long - probably in late May or early June - they, too, must have their growing tip removed, three or four side shoots being allowed to develop on each stem, and any other shoots which develop being rubbed ofl.

After flowering the plants should be cut down to about 450 mm (18 in) 111 height and a number selected to provide cuttings for the future. To save space it is best to label each plant individually and then to box them closely together in a 100 mm (4 in) deep box, sifting potting compost between them. In January you should reduce their height to 75 mm (3 111). Shoots will then soon begin to grow. Exhibition varieties will need to be propagated in January and February, and decorative varieties in February and March. The plants will happily overwinter in the cool greenhouse provided they do not remain wet for long periods.

pests and diseases The fungus disease known as 'damping off can be a tricky problem with greenhouse chrysanthemums: the blooms of soft plants that have received high-nitrogen feeds are particularly prone to it. The disease is greatly encouraged by wide fluctuations in temperature and by high humidity. Try to maintain the temperature at a steady 7 to to'C (45 to 51 F); on damp days keep the air circulating throughout the greenhouse (but beware of draughts). Of the pests, aphids are troublesome, leaf miners dc-tace the foliage, and earwigs damage the young shoots and eat the petals. Eelworm can be serious if the plants are grow~n in the garden soil.

Fuchsia Royal Velvet

Above Potted Cyclamen persicum hybrids in tlowe' Right fuchsia Royal Velvet makes an attractive centrepiece of a hanging basket

Cyclamen

In spite of the length of time between seed sowing and flowering, cyclamen are justly popular and can be grown in the cool greenhouse. They are available in a wide range of colours, with plain or variegated foliage, and some varieties are scented.

Plants for Christmas are sown from September to November for flowering the following year. Propagation temperatures of about 17 C {63 F) are best, and the young plants, one to each 90 mm in) pot, are overwintered at a minimum temperature of 15 C (59 F). To heat the whole greenhouse to rhis temperature would be expensive, so plan to let the plants remain in their propagating quarters as long as possible certainly until April. About this time pot on into 130 mm (5 in) pots, using)IP3 or a loamless compost. Once the plants have established themselves after potting on, they should be transferred to a lightly shaded cold frame. On warm days in summer the cold frame should be ventilated freely; this will encourage the development of compact plants without loose, straggly foliage. Return the plants to the greenhouse in September.

Seed may also be sown in spring, and the plants later ported into yo mm (3 \ in) pots in which they are allowed

Above Potted Cyclamen persicum hybrids in tlowe' Right fuchsia Royal Velvet makes an attractive centrepiece of a hanging basket to flower. Flowering will continue for several weeks, after which watering should he gradually reduced in order to dry off the corm (the swollen stem base), Corms may be restarted into growth in July and August in fresh compost. Make sure after re-potting that the top half of each corm is above the surface of the compost - if planted too deep the corms tend to rot. Cyclamen grown from corms in this manner should be discarded at'rer the summer flowering.

Cymbidium Repotting

Fuchsias

With its graceful pendulous flowers the fuchsia deserves a place in every mixed collection of greenhouse plants, for it provides colour over a period of many months. Although it is widely grown as a pot plant, it also looks well in hanging baskets and is attractive when grown as a standard.

The greenhouse varieties will overwinter satisfactorily in a minimum temperature of 5 C (42 F) and may be put outside in their pots for the warmer summer months. They are normally propagated by cuttings of new growth taken in the spring, but can also be raised from seed: in the latter case it is usual to propagate those it is desired to retain by cuttings.

Specialist firms list many named varieties in their catalogues and rooted cuttings are despatched in the spring. A good way of starting is to buy a named collection. Upon receipt pot them into yo mm (3^ in) pots and spray them regularly with water to help them become established. Plants destined for hanging baskets may be moved straight from these pots into their new quarters; two or three should be planted around the edge of each basket. Plants for flowering in the greenhouse will need to be potted on into 130 mm (5 in) pots in due course. The removal of the growing tip may be necessary at this stage if side growths have been slow to develop. These plants will need feeding throughout the flowering period. In late autumn the amount of water is reduced and the plants shed their leaves;

some cutting back of the plant, and removal of weak shoots, will reduce the amount of space they will take up in the greenhouse over the winter.

Plants to be grown as standards should have a strong-growing central leader. When they are moved into 130 mm (5 in) pots a 1.5 m (5 ft) garden cane is inserted into the pot and the leading growth secured loosely to this. Lateral growths are pinched out until the main stem reaches the desired height, usually just over 1 m (3 ft), when they are encouraged to develop laterally and form a balanced head to the plant. Fuchsias may take two growing seasons to reach this stage. The larger standards will probably require porting on into 180 mm (7 in) pots in later years.

46 flowering and foliage plants

Hardy Plants For Troughs

Asplenium bulbiferum is one of many species of hardy ferns that will grow in border soil that Is partly shaded by benching

Hardy Ferns

There Lire mimerous species at hardy ferns, most of them graceful plants which grow well in any greenhouse with a mixed cropping programme. When in pots they are ideal for setting off small displays of flowering plants, although generally speaking ferns like to have a free root run and will therefore grow better when they are planted in the border soil. They also look well in troughs, either free-standing or against a wall.

The ferns' natural habitats are shady places, and they do not like full sunlight; but they will grow in partial shade, and most of them will tolerate the conditions found beneath benching as long as some light is available. The rosy maidenhair Adiantum hispiduium is evergreen when grown in the cool greenhouse. If space is short it may be grown outdoors in sheltered situations so long as it is hardened off properly. Unlike many ferns it will tolerate full sun and is consequently ideal for bench-growing. Aspleiiium biilbi-fertim is a popular greenhouse tern which grows best in the border soil; some varieties will tolerate the cold and grow in an unhealed greenhouse. The fronds of the fern carry small bulbs, or bulbils (whence the species name), and young plantlets; these plantlets can be removed and used for propagation. Avoid overhead watering of asplen-iums, as it may lead to rotting. The ribbon or brake fern Ptcris cretica, one of the smaller species, is suitable both for the unhealed or cool greenhouse and for the home. It makes an excellent centrepiece in larger hanging baskets, whenfi its long, graceful fronds are shown off to advantage.

Ferns grow best in lime-free soils. It" you plan to use a loamless or John limes compost make sure it is a mixture suitable for acid-loving plants. Potting on can usually be done at the beginning of the growing season every year. Only rainwater should be used for watering or overhead spraying. Ferns are propagated from spores, best sown in the warmer part of the year.

Asplenium bulbiferum is one of many species of hardy ferns that will grow in border soil that Is partly shaded by benching

Hydrangeas

Well-grown hydrangeas are big plants, and some gardeners consider tliey look out of place in a small greenhouse. Certainly they may upset the balance of a mixed stand of plants; on the other hand, they are hardy and grow well in a cool greenhouse and have the advantage of occupying greenhouse space only in the winter and early spring months. Hydrangea macrophylla and its varieties that make up the Hortensia group are probably the most popular of this type, producing clusters of showy but infertile flowers built up into large globular heads in a wide range of colours and sizes, including pink, white, red, and blue. Another popular type is the lacecap hydrangea, whose flower head is flat with an outer ring of false-petals enclosing small florets.

Propagation is by cuttings taken in February and March from flowering shoots and rooted in a propagating frame in a temperature of about iN C (6s F), After rooting, the plants are potted into yo mm (3A in) pots using a lime-free compost. Once established, the growing tip is removed above the second pair of leaves. In early summer they are potted on into 130 mm (5 in) clay pots using a lime-free JIP3 or loamless compost; the newly potted plants are stood in a frame to harden off for a few days, then plunged outside. Around midsummer's day the side shoots that have developed should also be stopped above the second pair of leaves to provide a framework tor a well-shaped plant. Regular watering and feeding of plunged hydrangeas is essential.

The plants should be returned to the greenhouse in autumn after they have shed their leaves; at this stage they prefer cool temperatures. In late winter, as the days lengthen and day temperatures begin to rise, hydrangeas come into flower in the cool greenhouse and provide colour for many weeks, Atter blossoming, the flowering stems should be cut back hard. In early summer the plants are again plunged outside, tor the cycle to be repeated.

Hydrangea macrophylla makes a line pot plant, but because of its size it is mare suited to the bigger greenhouse.

Hydrangea macrophylla makes a line pot plant, but because of its size it is mare suited to the bigger greenhouse.

Miltonia Orchids PlantsGreenhouse Flowers Growing

Above The orchid Miltonia Knight Errant" provides flowers throughout the summer Right Passiflora caerulea racemosa, an attractive climbing plant that is propagated by cuttings taken in spring or early summer Of by seed sown in heat m February or March

Orchids

The orchid family accounts for almost one sixth of all the flowering-plant species, Although orchids were for long widely regarded as hot-house plants, many will grow in a cool greenhouse, Of these, Cymbidium, Odonto-glossum, Miltonia, and Papltiopcdih«n (formerly Cypripcdiitm) species and some others are nowadays within the realm of the average amateur gardener.

Cymhidiuin will provide sprays of flowers in the spring. Odontogiossuni (evergreen) flower in spring and summer. Some securing of the pseudo-bulb - the swollen base of the stem to the container with a fine wire may be necessary. The many species oi MH-tcrnui will provide flowers throughout the summer. Paphiopeditnm differ from the above in that they have no pseudo-bulbs; they flower after growth has finished, and propagation is by division.

Orchids are not widely grown by nurserymen and it is usual to purchase plants from orchid specialists. The fine exhibits staged at many shows provide an opportunity to compare named varieties, but their high cost deters many would-be growers. Initially 11 may he better to buy the less expensive seedlings and gain experience with them, although it will often be 12 to i s months before they come into flower.

Take the advice of a knowledgeable supplier when selecting plants for the cool greenhouse; the genera mentioned above include species that will overwinter happily if a minimum temperature of 7 C (4.S F) can be maintained. However, problems can arise in greenhouses with mixed cropping programmes, because on very hot days in the summer months the orchids will need to be protected from the direct rays ol tiie sun and the high temperatures. It may be best to move them lor a time to an unused deep garden frame, which can be shaded and ventilated to provide the optimum conditions, rather than upset the other plants.

The cultivation of orchids differs somewhat from that of the usual run ot greenhouse plants. An open compost of various mixtures of fibrous peat, sphagnum moss, and leaf mould was once recommended, but this is now being replaced by proprietary composts incorporating synthetic materials. The plants may be grown 011 a bench but are often grown in wire baskets or pans, suspended trom the glazing bars. They require no feeding but need repotting every two years. Water them regularly with rainwater in the summer months but keep them on the dry side during the winter months.

Above The orchid Miltonia Knight Errant" provides flowers throughout the summer Right Passiflora caerulea racemosa, an attractive climbing plant that is propagated by cuttings taken in spring or early summer Of by seed sown in heat m February or March

Passion Flora Art

Passion Flower

The passion flower (Pa ssi flora caertilca) is an attractive climbing plant suitable for growing in a cool greenhouse, or even 111 an unhealed one in the warmer parts of the country. It carries numerous Hat, open, star-like flowers of white, blue, and purple during the summer and is a half-hardy perennial usually raised from seed sown in heat in February or March. Germination is not always rapid and can take up to six weeks. When the seedlings are large enough to handle, pot them into 90 mm in) pots and later into 130 mm (j in) pots. In autumn the plants may be moved either into the greenhouse border or into large pots or tubs in readiness for flowering the following year.

Train the shoots up a light wire framework; they will eventually grow up to 5 m (16 ft) in length. They are not heavy, however, and do not cut out too much light. Pruning, in February, consists of removing the weak shoots and shortening the previous year's grow th on the remaining shoots by about one third.

Propagation is also possible by taking cuttings of young shoots in the spring and early summer; they are not difficult to root 111 a propagating ease.

_s0 flowering and foi tar;e plants

Pelargoniums

Pelargoniums are high on most people's list of popular greenhouse plants, tor the flowering types provide colour throughout the summer and in some cases well into the autumn. They may be classified as 'zonal', with leaf margins ot a different colour from the main colour of the leaf (these are commonly called 'geraniums'); 'show', which are widely grown for their attractive semi-double flowers; 'fancy', somewhat smaller versions of show pelargoniums; 'ivy-leafed', with attractive ivy-shaped leaves, sometimes variegated, which trail or climb and are consequently ideal for incorporating in hanging baskets; and 'scented-leaved', grown mainly for their scent.

It has been customary to propagate pelargoniums from cuttings taken in July and August, but owing to poor selection some stocks have deteriorated over the years. Leading commercial growers have made strenuous efforts to improve the quality of plants, but with the introduction of F hybrids, raised from seed sown in heat in January. many amateur gardeners have taken to raising their own. Seeds need to be in temperatures of 21 to 22 C (70 to 73 F) to germinate, and such temperatures are attained without difficulty in a small propagating frame. Once potted in yo mm (3 J in) pots they grow on satisfactorily in lower temperatures. Highly commended by the Royal Horticultural Society are the 'Carefree' hybrids, which ultimately grow to a height of 450 mm (1S in), and the somewhat shorter 'Sprinter has been internationally acclaimed.

A few standard plants are always useful for display purposes and the show types are not difficult to train. Select strong-growing young plants and remove all side growths. Tie the single stem that remains to a cane; it w ill grow to a height ot .11 least fioo mm (2 ft) in the first year. Before they recommence growth in the second year move the plants to bigger pots and allow the single stem to continue growing up to the required height: a clean stem of just over 1 111 (3 ft) makes for a useful plant. Once this height has been attained side shoots are again allowed to develop. Prune the top of the plant annually to keep an open framework, but on no account put the knife into the main stem.

Roses

Commercial growers devote a considerable acreage of glasshouse space to roses, which are grown in the border soil and remain in situ for several years. Requiring minimum temperatures in winter of 7 to 10 (.! (45 to 51 F), the rose is suitable for growing in the home greenhouse in pots, not the border.

Bare-rooted plants should be purchased from a rose grower early in the lifting season, possibly November, and his help should be sought in choosing first-quality plants with a strong growth. It is best to avoid container-grown plants, which may have been potted into a compost unsuitable tor a long spell of intensive growing. Any field soil that remains 011 the roots w ill need to be washed off and the plant potted into a 200 mm (X in) clay pot using JIP3 or a loamless compost; with the former, good drainage must be provided. Some root trimming may be necessary to fît the roots into the pot; any cuts should be made cleanly using a sharp knife.

Prune the plants before they are brought into the warmth at the turn of the year, when a maximum temperature of 10 C (^1 F) should not be exceeded. There will he some flowers in the first spring flush, but considerably more 111 later years. Plunge the plants outside in their pots for the summer and autumn months and rehouse them earlier in the second and subsequent years. As is the case with all plants grown in containers, liquid feeding is important and feeds with a high potash content are best used at and near flowering time.

Bulbs

A large number oi flowering plants can be grown from bulbs in the greenhouse. Perhaps the most popular among amateur growers arc narcissi, tulips, and hyacinths, all of which will thrive under 'cool1 greenhouse conditions. Choose any of the tine modern varieties of each, but avoid planting bulbs of different varieties in the same containers. The earliest-flowering are the 'prepared' bulbs, but they are more expensive owing to the temperature-con trolled conditions in which they have to be stored after lifting. Earliness is. indeed, their only advantage: the quality of their flowers is in no way superior to that ot' normal bulbs, which 111 any case will bloom much earlier in the greenhouse than specimens planted in the garden.

Buy big bulbs for green house flowering, and pot them in September or November in the recommended composts. The depth of the container is important, because there should be at least 25 mm (1 in) of compost below the base of the bulbs. The top quarter ol the bulbs can rise above the surface of the compost without affecting their eventual flowering performance, (-lav pots are the most attractive containers for these flowers. On the other hand, more or less any type of suitably shaped container is satisfactory if you are growing bulbs to provide cut flowers (1 have used well-washed fish boxes with success). Whatever containers you use. make sure that they provide good drainage.

Atter potting, water the bulbs well. Then plunge them outdoors in a sheltered position, covering them with a 25 111111 (1 in) layer of peat, ami heap about 100 nun {4 in) of garden soil on top. When the plants have developed a good growth of foliage, bring them into the greenhouse. The foliage will need supporting; small twigs are adequate for narcissi, but use split bamboo canes for tulips and hyacinths. After flowering, the bulbs may be planted out in the garden.

inexpensive Flowering Plants

A wide range of greenhouse plants may be raised from seed. As only a few plants are normally required they are sown in pans and germinated in heat in the propagating frame. The usual routine is initially to pot the more vigorous seedlings direct into yo mm {31 in) pots, and to prick out the weaker ones into boxes where they are allowed to grow on for a while before they are potted tor the first time.

As the plants grow and the roots till the pot. a second potting into 130 111111 (5 in) pots is made and most plants wiU perform perfectly well in tins size of pot. Liquid feeding ot the plants is important, especially during the periods of rapid growth. With loamless composts it is important that feeding begins early. Some popular examples ot this group are described overleaf.

Potting on pelargoniums into 125 mm (5 in) pots for a summer display in the greenhouse

Potted Zonal PelargoniumsAntirrhinum Madame Butterfly
Antirrhinum ma/us Madame Butterfly' makes an outstanding display under glass, with flower spikes up to 1 m (3 ft) long

antirrhinum The snapdragons arc normally associated with schemes of garden bedding, but when grown in pots in the greenhouse they can provide an outstanding and colourful display for long periods. The variety 'Madame Butterfly1 grows up to i m

(3 ft) high and the double florets, if undamaged by wind or rain, are particularly striking. Each plant needs the support of a 1 m (3 ft) long cane and this is best inserted behind, but close to, the stem early in its lite. Paper-covered wire ties put on as the stem grows will be inconspicuous .it flowering time. Set. .is are sown from January to March in heat and the plants moved in stages into 130 mm (,s in) pots to flower. They may be used also as cut flowers.

Many other garden annuals can be treated in a similar manner.

begonia The fibrous-rooted begonias are half-hardy perennials best raised from seed and sown in heat from January to March. If sown thinly the more sturdy seedlings may be potted directly into <jo mm (3 I in) pots, 111 which they will flower. Those remaining can be pricked out into a seed tray, allowing 110 more ih.111 32 per box, for summer bedding outdoors, Mo*.t varieties provide numerous flowers for long periods. Propagation is also possible by taking cuttings of young shoots 111 the spring from overwintered plants.

Right Begonia semper florens Flamingo is one ol the fibrous-rooted begonias which can be inexpensively raised from seed

Begonia Semper Florens

Right Begonia semper florens Flamingo is one ol the fibrous-rooted begonias which can be inexpensively raised from seed

Red Flowering Perpetual Begonias

Calceolarias piovide a fma display in late wmier and early spring

CALCEOLARIA 1 lie slipper flower seed is sown in June, The young plants do not like high temperatures and are best grown in a shaded frame in the summer months. House the plants just before the onset of the autumn Iionis, toi temperatures below freezing will kill them. Il the frame is heated they may remain in it for several more weeks. A range of varieties is available and will provide colour for several months in later winter and early spring. The plants do not tolerate wet foliage, so avoid spraying overhead; neither do

Calceolarias piovide a fma display in late wmier and early spring they like too much bright sunshine, and shading is sometimes necessary. The golden rule with Calceolaria is to grow cool, not hot.

capsicum Often listed as the ornamental pepper. Capsicum is grown tor the brilliant colour of its fruits rather than for its flowers. Sown at any time during the first six months of the year, when propagating space allows, the plants fruit best m 180 mm (7 in) pots. They need not occupy the greenhouse in the warm summer months, but if brought indoors before the frosts they will provide fruits through to Christmas as long as they are grown in cool rather than cold conditions.

cineraria These arc available in a wide range of brilliant colours. They may be sown in pans or boxes in a cold frame from April to August, The early flowering 'Spring (¡lory' strain, sown in June, will flower within six months, and if successional sowings are made through to August succcs-sional flowering will continue through to April. The flowers last for eight weeks or more and the plants grow to a height of 200 to 250 mm {8 to 10 in). Aim to grow cool, but not in a cold greenhouse, in order to get compact foliage; high temperatures lead to soft, leggy growth.

FREEStA Although they may be grown in pots for display purposes, it is more usual to use t'reesias as cut flowers. In the former case grow them in 1,10 mm (_s in) pots; if you require cut flowers grow them in wooden boxes at least 130 mm (5 in) deep. They grow best in u 11 heated or cool greenhouses and may be raised from seeds or conns. Seeds arc sown from March to June in a potting compost and spaced no less than 25 mm (1 in) apart; they arc not transplanted. They flower from autumn well into the winter months. Alter flowering, growth will continue for some time, but later, when foliage begins to die down, slowly reduce the amount of water and give up feeding altogether. The plants ultimately dry off and the cornis which they have developed can be put aside for grow ing in future.

Frecsias grown from corms will flower throughout the winter months in the greenhouse it the minimum temperature is above 10 C (ji F). Augustplanted conns normally flower about January; September/October-planted corms flower m February but need to be plunged after planting.

Pink Berry Type Flower Tree

Above Svlanum. I he Chustmas cherry Daily syringing trom (towering lime encourages a good display o( berries Right frme.^a * kewensia hybrids grow in a cool greenhouse and provide winter flowers impatiens sultani The busy lizzie is an easy-to-grow plant that flowers perpetually through the summer. Many varieties are now available and the F( hybrids are greatly superior to earlier strains; the award-winning 'Imp' strain is especially worthy of note, ¡tnpaiiens are best treated as half-hardy annuals; sown in heat m early spring, they w ill normally germinate in 14 to 21 days. Although usually grown as pot plants they also look well in mixed hanging baskets.

primula Many species of Primula provide a delightful show of colour during the winter months, although their seeds are unusually small and need to be carefully handled. Suitable species for the cool greenhouse include P. x kewensis, P. obtonica, P. nuihuoidis and P. sinensis. For winter flowering they are usually sown in May. P. mala-coides (fairy primrose) is often preferred for spring flowering, in which case it should be sown in July. A word of warning: P. obconka may cause a rash to develop on people who handle the plant. Although you may not suffer in this way, you should think twice before giving examples of this attractive species to a friend.

Above Svlanum. I he Chustmas cherry Daily syringing trom (towering lime encourages a good display o( berries Right frme.^a * kewensia hybrids grow in a cool greenhouse and provide winter flowers solanum CAPSlCASTRUMl he Christmas or winter cherry is a small, berry-bearing shrub ideal as a Christmas pot plant. Sown in heat in February, the seedlings are potted singly into yo mm {3^ in) day pots when large enough to handle. Unless they are one of the dwarfing varieties, pinch out the growing tips when the plants are 75 mm (3 iu) high to encourage side shoots to develop. Provided the weather is not cold they may lie transferred to a frame as early as May and are best plunged. They should be grown as cool as poss-i b I e during the s u m m e r m o n t It s. Syringing at least once a day, starting at flowering time and continuing during the summer, is recommended to obtain a good display of fruiting berries, Rehouse the plants in late September; they require temperatures of 7 to io°C (45 to 5i°F).

The following are brief notes on some additional flowering plants ot more than ordinary interest that can be grown in the greenhouse:

Achimenes PlantAchimenes Hybrid Double

achimenes (michelssen hybrids)

Sow seeds in February/March. Flowers mid-summer to autumn. Repot in January.

begonia x tuberhybrida The tuberous-rooted type, as opposed to fibrous-rooted forms (see above), lie-quires minimum temperature ot G (s > F), Start un damp peat in mid-March, and then pot. Summer flowers require shade. Overwinter tubers in a dry peat/sand mixture, preferably in the home.

CHLOROPHYTUMCOMOSUM V AltlF.CiA-TUM {SPIDER PLANT) I lardy pot plant with long, grass-like leaves with broad central white strip. Grows plantlets that are easily rooted. Repot annually.

coleus (flame-nettle) Valued for its bronze-red or deep pink leaves. Grow from seed, Remove any flowers that form. Propagate from cuttings.

ficus elastic a "robust a* TllC India-rubber plant makes fmespecimen plants for the home. Needs a warm greenhouse, 1.1 C (55 F), and good but indirect sunlight. Dei not over water. Glean leaves regularly with proprietary leaf cleaner or mixture ot i part milk to 2 parts water.

GER It ERA J AMESONIi (lit ANSVAAI

daisy) Colourful perennial hybrids with large, daisy-shaped blooms. Sow-seeds in February/March, Repot annually, Propagate vegetatively by side shoots.

sinninuia speciosa ((¡loxiniai Perennial with fine, hell-shaped flowers and attractive dark-green leaves. Choose Fi hybrid seeds and sow early in the year in warm greenhouse. Tubers may be kept from year to year; or propagate from leaf cuttings.

hedera helix (ENCii.isii ivy) M an y attractive varieties available. Grow in cool greenhouse as pot plant or in border, and allow to climb. Good for hanging baskets. Can eventually be planted outdoors.

Picus elastics The upper and lower surfaces o1 the leaves should be cleaned regularly The varying leaf sizes ot this example indicate that it has been fed irregularly.

K.AL ANCHOE SPECIES 1 lardy winter-flowering plants with scarlet blooms, growing well in small pots. Perennial, though generally with poor flowers after first season. Sow seed in early spring; house plants in frames in summer. Some species develop plantletson edges of leaves; others can be propagated by cuttings.

mimosa pudica (THE sensitive pl ant) Its small, feather-like leaflets fold Up tightly it touched, slowly reopening. Grow as an annual from seed in the spring in warm greenhouse Sow seeds in sandy compost.

peperomia cape It ata Small, attractive pot plant with dark green, heart-shaped, crinkly leaves and white (lowers. Propagate by leaf cuttings in warm greenhouse.

SA1NTPAU1 IA |Al rk AN VIOl el i A worldwide favourite, with hundreds of varieties, flowering almost throughout the year in right conditions. Minimum temperature l6°C (f>ol); but may be moved into cool greenhouse in summer; good light but with some shade from bright sun. Water moderately, with warm water. Propagate by leaf cuttings.

STtl'HANOTIS FLORIBUNDA Vigorous evergreen climber with strongly scented tubular white flowers 111 summer and autumn. Propagate by cuttings of young wood. Prune heavily to restrict growth.

streptocarpus (triumph hyi1rids) Colourful trumpet-shaped flowers ot violet, blue, pink, red, or white in summer, Raise from seed in lanuarv in warm greenhouse, flowers need warm conditions, shaded from bright sunlight.

TRADESCANTIA SPECIES Pol plants with colourful trailing foliage, different varieties having silvery, gold, pink, or purplish leaves. Propagate by cuttings; use about five rooted cuttings in each pot for best effect. Grow in warm greenhouse with good light.

Right above SmMpduit.i rriiiln i Imp display but need a minimum ot 1 ii C (tiO F) Right below January sown Streptacarpua hybficts flower in late summer

Square Foot Gardening GreenhouseSquare Foot Gardening Greenhouse

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