Growing methods

There is an increasing number of alternatives to growing in the border soil. Plants have been grown 111 pots since the early days, but as pot prices rise the polythene growing bag is becoming .1 popular and economic alternative. These sausage-shaped bags are bought ready filled with a complete compost and are well worth using if the border soil is poor or 111 need of sterilization or where it is advantageous to be able to move plants around.

Watering is a less simple operation than many people realise. If possible water should be applied in small droplets, and both the watering can and the hosepipe should be fitted with a rose; trickle irrigation is, of course, a suitable alternative. After the initial flooding, the aim should be to keep the soil moist, but not sodden, and to ensure that there are no dry patches. The grower with a glass-covered greenhouse also needs a syringe, which will deliver a fine, almost mist-like spray over the foliage during warm, sunny periods; this creates a good growing environment for the plants. The inexperienced gardener should ask a professional to demonstrate exactly what is required, or should visit the greenhouses of his local parks department. In polythene-covered structures constant high humidity may be a problem. It is caused by

To use all available space, pot-gcown sweet peppers may be grown between tomato plants.

Sweet Peppers Space Needed GreenhouseImages Polythene Greenhouses

the beads of water which build up on the polythene sheet, and the remedy is less syringing ot the plants.

The larger food plants need to be supported from early on in their life. Most can he loosely secured to a supporting cane. Alternatively, plants such as tomatoes can be supported by strings tied loosely to the plant just above soil level and secured at the other end to stout glazing bars or root framework : as the plant grows the string is wrapped round the stem.

Clearing a crop when it is finished needs to be done carefully. At this stage of their life the plants may he infected with disease organisms both above and below soil level. They should therefore be cut down gently and loaded straight into a harrow. When forking out the

Left Preparing bordeir B'oil I Alter digging out one sent depth bruak up subsoil; 2, 3 Raptaca topsoil. digging in plenty of organic matter; 4 Thoroughly soak the border Above Growing bags made of polythonti do away with the need to sterilize border soil roots, remove as much of the root growth as possible.

Tomatoes

Tomatoes are undoubtedly the most popular greenhouse crop and constitute the cornerstone of many greenhouse programmes. The flavour of freshly picked tomatoes is considered by most people to be better than that of fruits that have passed through wholesale and retail channels. In heated green houses tomatoes may be harvested from May to October; in unhealed structures from August to October. The yield varies enormously, but it generally lies in the range of .i to 7 kg (fti to 15! lb) per plant, depending 011 whether the crop is grown without or with heat. A common mistake among amateurs is to grow too many tomatoes. If you find yourselfwith ,1 surplus, consider deep freezing or, with the green fruits, making chutney. It'tomatoes are grown in the same border year after year, yields will almost certainly decline markedly after the second crop owing to the build-up of diseases in riie soil. Newcomers to tomato growing often obtain heavy crops in their first year only because the soil is tree of such harmful organisms.

varieties The choice is wide, with each variety having different points of merit. If you have .1 small greenhouse it is best to go for compact-growing plants which have their trusses close together. Varieties are available which are resistant to the disorder known as greenback, and first-cross hybrids may give heavier yields owing to their 'hybrid vigour'; a couple of recommended examples are 'Eurocross lSli' tor heated greenhouses and 'Alicante' for unhealed ones. Grafted plants are available in some areas; the variety, raised in the usual manner, is grafted on to a form of wild rootstock when both are about the thickness of a pencil. The wild rootstock has some resistance to the more common soil diseases, and

Examples Budding Plants Rootstock

Left Preparing bordeir B'oil I Alter digging out one sent depth bruak up subsoil; 2, 3 Raptaca topsoil. digging in plenty of organic matter; 4 Thoroughly soak the border Above Growing bags made of polythonti do away with the need to sterilize border soil

Sterilization Crops Images

'Gardeners Delight' tomatoes, with peppers consequently in some cases offers an alternative to soil sterilization.

propagation Temperatures of (Inorder of 21 G (71 F) are needed in the early stages of propagation, and minimum day temperatures of 1S C ('>5 F) when the seedlings are potted. Tempera tui e* as high a^ these are expensive to maintain in the early months of the year, and an alternative method is to buy in plants raised by ,1 nurseryman. Although this reduces the satisfaction derived from raising one's own plants, it is better to do this than to propagate plants at lower temperatures than those recommended : conditions experienced by the plant early in its life affect the potential yield of the lïrst three trusses. If plants are raised from seed and

  • Gardeners Delight' tomatoes, with peppers early tomatoes are required, a late-November or early-December sowing is the rule for a heated crop. Sowing in heat in late February or early March will provide plants for a cold-house crop. Tomato propagation is straightforward: sow seeds thinly in boxes or pans; later, pot the seedlings into yo
  • m pood crops mm (3^ in) pots, and finally plant from these into the border or containers.

cultivation Where plants are to be grown m tlie border, thorough soil preparation, as described above, is essential because tomatoes are gross feeders. Planting in cold, wet soil will cause a major setback in growth, and it is preferable to transfer the plant to a bigger pot and stand it out on the border in its final position; planting can then take place when the soil conditions are more suitable. Plant 450 mm {[N in) apart: closer spacing greatly reduces air circulation, which c.111 create growth problems, hi narrow borders two rows may be grown il the plants are staggered ll is essential to ensure that the plants are not dry just before they are planted, and immediately after planting they should be watered in to settle the soil around them.

Tomatoes crop well in growing bags. The compost in these bags is scientifically formulated, with the correct plant foods already added. The bags warm up more quickly than the border soil, and consequently the plants gel oH to a good start. Bags can be put close together while the plants are small and placed in their final positions later — a valuable asset when greenhouse space is scarce in the spring. The roots of bag-grown tomatoes do not penetrate into the border soil and consequently do not contaminate it Support the plants by stake or string soon after planting out.

The side shoots that grow 111 the leaf axils (where the leafjoins the stem) must be snapped out when small, and this is best done early in die day when the plants are turgid. The first trusses of early crops sometimes do not set. and the use of fruit-setting hormones is an invaluable aid.

The tomato plant needs moist atmospheric conditions lor a short while each day to assist fruit setting, and this is best achieved by spraying over the plants with a syringe, preferably early in the day. You should water the plants by hand two or three

Right above Tomato plants need to be supported by siring (as here) or by a stale Right below Tomato side shoots should be removed when small Do this early m the morning, when the plants are turgid times a week (daily if automatic irrigation is used), ensuring that sufficient water is supplied tor the subsoil not to dry out. Healthy plants should not require shading: if they wilt in bright sunshine, look for another cause. Is the plant short of water? Has it a healthy root system? Tomatoes like a minimum night temperature of 12 C (>4 F) and a minimum day temperature of ix C (65 F); if automatic vents are fit ted they should be set to open at 22 C (73 F). Regular liquid feeding of the plants throughout their period ot grow th is essential; a number of proprietary brands of feed is available.

The fruit, with the calyx attached, is best picked before it is fully ripe it' the plant is heavily laden. Common fruit disorders are blossom-end rot and cracked fruit, which can both be attributed to deficiencies in watering.

Automatic Greenhouse Cover

food chops 63

Cucumbcrs

Cucumbers are widely grown under protective cover by amateur gardeners, and they will produce satisfactory crops in both heated and indicated structures. If grown well a couple of plants will provide the average family with an adequate supply of the fruit throughout the summer season. Cucumbers like very warm, moist conditions and for this reason do not grow well along side many other food crops. If you wish to grow them with tomatoes you would be well advised ro screen off a small area of the greenhouse with thin polythene so that the cucumber plants have a growing area all to themselves. In my experience cucumber plants grown in a polythene-covered greenhouse grow quite satisfactorily without such a screen, possibly because ot the higher natural humidity, In fact, I fav our growing them on their own in a garden frame, where I obtain results just as good as if they were in the greenhouse.

varieties Most varieties of cucumbers produce male and female flowers and the male flowers have to be removed daily to ensure that the female flowers are not pollinated : if seeds are produced within the cucumber they give a bitter taste to the fruit. This time-consuming chore is now a thing of the past if varieties are chosen which produce only female flowers: 'Fernspot' and 'Smiex' are all-female F] hybrids highly recommended for growing in the greenhouse or frame. As with tomatoes, relatively high temperatures are required in the early stages oi propagation and it may be preferable (and cheaper) to purchase plants from a nurseryman ready for immediate setting out. Buying in greenhouse plants needs rather more care than buying in bedding plants. In particular you should be satisfied that the plants have not been exposed to cold, windy conditions for any length ol time; those that have spent several days outside an exposed shop front should be left well alone, cultivation Cucumber plants art-very fussy about the soil in which they are cultivated. It is customary to prepare a raised bed, or mound, consisting mainly ot fairly well-rotted, strawy horse manure il it is available; alternatively, you can use fairly well-rotted garden compost, In both cases the presence ot partially decomposed plant material is an asset. Put a layer of good topsoil or potting compost on top of the bed and set the plants into this provided the soil temperature is not too high. The decomposing matter will continue to generate some heat tor a few weeks, which will encourage rapid growth of both roots and stem. The raised bed sinks with decomposition and should be topped up from rime to time with more organic matter although it the plants are grown in frames it may he impossible to do

For best results cucumbers need to be grown on mounds of well-rotted horse manure or compost in very warm, moist conditions To Support the cucumbers, tie the stems with raffia 10 a cane or wire frame

Tie Supports For Cucumbers GreenhouseTie Supports For Cucumbers Greenhouse

this without causing them damage.

Take care in supporting the plants in the greenhouse to avoid strangling them as the level ofrhe rooting medium sinks. Supports may be of cane or wire, and in either case the plant should be secured to its support with raffia or paper-covered wire ties.

Cucumber plants like plenty ot water and are gross feeders. They benefit from a weak plant-food solution at every watering. A high-nitrogen feed is best, because otherwise the plant will be starved of nitrogen as the organic matter in the bed decomposes. Allow the temperature in the greenhouse or frame to rise to 2fi t' (79 I:) before opening the ventilators, and maintain a humid atmosphere by syringing the plants two or three times a day in hot weather; the greenhouse path should also be kept moist during the daytime. If the plant is growing well, shading should not be necessary.

Some training ot the plant is essential. The main stem is allowed to grow naturally: the side shoots are trained to grow horizontally and on either side of the main stem. It is best to remove the lowest six laterals during the early stages of growth; the remainder are stopped after the second leaf has formed by pinching out the growing tip. Cucumbers are allowed to form 011 these lateral branches. As the season progresses the laterals may send out sub-laterals which should be stopped after the first leaf has formed; they will also bear fruit in turn. I here are conflicting views as to whether it is wise to allow cucumbers to develop on the main stem; 1 myself allow all fruits that look healthy to develop.

Red spider mite is perhaps the most troublesome pest of this crop; if supporting canes are Used, colonies of the mite tend to build up in them. This pest can be controlled by sprays or fumigants, but it should be noted that cucumber plants are harmed by sprays containing I )DT.

When you clear the crop, spread what remains of the rotted compost over the border; it will enrich the soil and benefit subsequent crops. Some cost-conscious gardeners prefer to bag Up the compost tor use as a potting soil, but while it usually gives saris-factory results tl used in this way it has drawbacks because the essential plant foods may be our of balance.

Lettuce

In recent years improvements in the rapid transport ot food crops have been such that we have become accustomed to eating green salad plants such as lettuce throughout the year. In fact, the ho me greenhouse gardener can now provide lettuce for much of the year if he selects his varieties with care; in particular, fast-growing varieties raised in protected cultivation produce tender, succulent leaves. Relatively easy to grow, lettuce does exceptionally well under polythene and where soil-warming cables are used.

Growing Butter Crisp Lettuce

TYPts and varietibs There are three main types: 'butter-heads', round-hearted lettuce with soft leaves; 'crisp-hearted', which have curled leaves; and 'cos', with straight upright leaves w Inch form a loose heart. Many varieties are listed by seedsmen, and the two main factors that will determine your choice arc whether the crop is to be grown cold, with gentle heat, or at fairly high temperatures, and the time of year of sowing and harvesting. The Glasshouse Crops Research Institute has raised ,1 number ot varieties that can be recommended; look also

Growing Greenhouse Borders

for varieties carrying the award ot merit of the Royal Horticultural Society (AM. RHS). Make sure that the varieties selected are recommended for growing indoors.

propagation Seed may be sown directly into the border soil, as with outdoor lettuce, but this does not make for the best use of available space. It is

Led Three popular forms of lettuce butter head, crisp hearted .i"'l r us 1 ns lettuces make quicker lighter hearis 1! tied loosely with string or raffia jusl when hearting begins Below Moving seedlings from the seed trey into thair firs! pot If this is carried out on the benching, it is advisable to use a polythene sheet to avoid spilling compost on to the bench Qravel better to sow in a seed tray and, as soon as the plants are big enough to handle, to move them to small peat pots. When doing this, handle the plant by a leaf and not by the stem, for the latter is very tender and easily bruised. Try to plant it at the same depth as it was in the seed tray, and settle the compost around it by lightly watering overhead.

cultivation The plants will grow happily in these pots on shelving or benching for four to six weeks. They are then put out into the prepared border, spaced 230 to 300 mm {9 to 12 in) apart, depending on vigour ol variety and type. Regular liquid feeding with .1 soluble plant food will help them to mature quickly. Lettuce like plenty of water and will succumb to a number of disorders if the growing medium dries out. When applying water, however, do so with care to avoid splashing soil 011 to the foliage. They also prefer alkaline soils to acid, and lime should be worked into the border as part of the preparatory work. Lettuce like good light conditions but not excessive heat. Ventilate the greenhouse in summer when temperatures rise above about 22 C (72 F). Slugs can he .1 problem, and the old gardener's remedy is to apply well-weathered soot to the soil surface just before planting; if this iv not available use a slug bait. Botrytis, or grey mould, is the major disease, particularly ofovcr-wintering lettuce in unhealed conditions; greenfly is the most troublesome insect pest.

66 food crops

Courgettes

Courgettes, a type of small marrow, were once considered .1 gourmet's dish but are now widely grown tor the family in the vegetable garden. They respond well to a little protection, producing numerous tender fruitlets from June through to October, When fully grown the plant can be as big as 1 111 {l tt) across, and as such is not suitable for the small greenhouse where space is at a premium. Courgettes are excellent for growing in the polythene greenhouse or in the garden trame.

varieties The variety 'Green Bush' is my favourite. It is one ot the earliest, has the Award of Merit of the Ri IS and the added vigour of an Fi hybrid, and is recommended tor freezing.

propagation Seeds may be sown 111 late March in the south of England and in mid-April in the north. Sow one seed per 90 mm (3 j in) pot filled with John Innes seed compost or a proprietary peat/sand mixture. A little heat is required; greenhouse border space can be saved by not planting out until such time as the roots almost till the pot.

cultivation Build a small mound of well-rotted compost on top of the prepared border soil and plant into this. Space plants at least fioo mm (2 ft) apart, planting in May if space allows. Plants surplus to requirements may be hardened off ill the cold irame and planted outdoors when the danger ot frost has passed. If the plant grows so vigorously that it seems to be getting out of hand, cutting the main stem back hard will check it without killing it. Courgettes will tolerate a wide range of temperatures, and consequently they fit in with many cropping programmes. As with almost all vegetable crops grown 111 protected cultivation, they welcome a syringing overhead on warm days. Grown well they are rarely troubled by pests; like Other marrows, however, they are susceptible to virus diseases. It is essential to pick the fruits while they are small: 100 mm {4 in) is the ideal length.

Right above Courgettes grown under glass fruit long before those grown outside Right below Ilervest the courgettes when thev are about 100 mm (4 in) long

Watermellons Grown Overhead Tressel
A

Melons breeder. Few gardeners are likely to

Once looked upon .is suitable only for want to plant .1 greenhouseful of rnel-

tbe warmer greenhouse, melons can ons, but two or three plants worked now be grown in un heated green- into the summer cropping programme houses, frames, and cloches on all but will produce a moderate harvest of the coldest sites. This has been made fruits that will be welcome in the possible by the work of the plant August to October period.

Can Grew Candalupes Stick

varieties Selection of variety will depend upon whether the plants are to be grown with or without heat. In the former case choose from green , white-, or scarlet-fleshed varieties; for colder conditions stick to the cantaloupe types such as 'Sweet-heart'.

propagation For the few plants that will be required it is best to sow one seed per 90 mm in) pot in April the early part of the month for heated crops, the end of the month if the plants are to be grown on without heat. Propagating temperatures of around 21 C {71 F) are required initially; after the first pair ot true leaves has formed, growth can continue at slightly lower temperatures. As soon as the roots begin to crowd the pot, the plants may be planted out m the border soil; if they are to he moved to cold frames or cloches, however, the plants will need first to be hardened on, cultivation Harder preparation is similar to that described above for cucumbers; alternatively, plants may be grown 111 growing bags, and three plants will grow comfortably in each, (¡rowing bags are especially suitable if you wish to grow melons on benching. In the greenhouse the plant will need support while it is still in its pot. Some training of the plant is essential: in frames and cloches pinch out the leader at the fifth leaf, and stop the lateral shoots that subsequently develop at the third leaf; 111 the greenhouse train the leader upwards.

Melons need to be pollinated by hand. Each female flower has a tiny fruit at its base. This is most easily pollinated by plucking otfa male flower, removing its petals, and brushing the pollen into the female. Syringe the plants ,it least once .1 day. As fruits form, support those growing in the greenhouse with small nets and those in frames and cloches by placing a piece ot slate or glass beneath each developing fruit. Start regular liquid feeding as soon as the first truits form (earlier it the plants are being grown on organic mounds).

Pot-grown melons need training up canes from an early stage The individual fruits may later need to be supported ro prevent ihem breaking off their stem The easiest way to do Th 1 a is by tying them into siring nat bags.

Images Greenhouse Coldframes

Sweet Peppers

Plant breeders have responded to the need for new varieties as the demand for peppers grows steadily year by year, and the recently introduced hybrids have performed well not only in greenhouses but also in cold frames. Two recommended varieties are'Early Prolific* and 'New Ace'. Peppers grow exceptionally well in polythene-covered structures. Seeds are sown individually in small pots in March and propagated in temperatures similar to those maintained for tomatoes.

Well before the plants get pot-bound they should be moved into i 30 mm (5 in) pots. Planting when the first flower bud is 2 to 3 mm {about J in) in diameter gives the best results, and plants should be spaced 330 mm {13 in) apart in a single row, the site having been prepared well beforehand in the same way as for cucumbers. Frequent syringing on warm days will provide the humid conditions which help the fruit to set.

Peppers are normally harvested between July and October and should be picked when green if maximum yields are required. If left 011 the plant they will turn red, but in the process they will sap the plant's energy, and may reduce its potential yield by as much as one third,

Aphids can be a major pest of the crop; the main disease affecting sweet peppers is Bo try lis (grey mould), which can often be prevented or reduced in effect if the plant and its surroundings are kept as clean as possible.

Lett Pot-grown peppers are normally picked green ¡n mid-summer to early autumn Allowing them to remain on the plant until they have turned red will considerably 'educe the potential yield of each plant Right Salad crops grow especially rapidly under polythene-covered structures and are consequently tender and tasty Varieties of many salad crops have been bred especially tor intensive cultivation, allowing two crops per season to be grown

Images Carrots Radish Turnip Beetroots

Beetroots, Carrots, Turnips, and Radishes

Provided suitable varieties are chosen take your seedsman's advice on this -these crops, more usually grown out of doors, can all be cultivated under glass or in polythene-covered greenhouses.

Under these conditions the more rapid growth that results means more tender vegetables and, in warmer regions at least, the possibility of two crops per season instead ot one.

Varieties of all these crops have been bred specially lor intensive cultivation of this nature, and their most noticeable feature is their compact toliagc. Root-crops like rich but not freshly manured soil, and the seed may be thinly broadcast on the border and lightly raked in rather than being sown in drills as is Usual outdoors.

The food crops discussed above arc from plants that spend most if not all their lives under glass or polythene. Below are some plants that are grown mainly outdoors but can be brought into the greenhouse for forcing or other purposes. This is an interesting and important secondary role for the greenhouse, but it should not be allowed to interfere with your prime-purpose cropping regime.

ft luibarb

'Timperley Early* is one of the earliest varieties of outdoor rhubarb. It can be forced early in the year in the greenhouse With little difficulty as long as space is available to provide the rather special conditions the plant requires.

The plants are grown in the open ground in the usual manner and provided with a plentiful supply of wellrotted organic matter during the growing season. Apply this to the soil surface and allow worm activity to incorporate 11 in the soil. Pulling of rhubarb sticks from plants that are to be torced the following winter should stop early in the season to ensure big, plump crowns,

In November the selected crowns, which should be at least two years old. must be exposed to frost to bring on their brief dormant period. Soon after Christmas carefully dig up the crowns and move them to the greenhouse, where they should be replanted in a dark place beneath the staging, tor instance. Water them well to settle the soil around them. Depending on the amount of heat available, the buds will soon start into growth; they should not be exposed to light except for picking, and the sucks are pulled when they arc about 2.so mm (10 in) long.

Slugs may be troublesome and slug bait should be put out as a preventive measure. After cropping the crowns are best thrown away, as this forcing treatment exhausts them.

Rhubarb being torced in the dark beneath a greenhouse bench Crowns of outdoor varieties selected tor forcing should be brought in from the k tchen garden and planted in the border soil m the last days ot December

Sowing Peas Indoors

Early pickings ot peas may be obtained by sowing seeds in (roughs which have removabla boliom boaids Raised in heat, the young plants, still in the trough, are hardened off before they are planted out

Peas

Many people still prefer fresh garden peas to tinned or frozen ones, and winter sowings outdoors of the hardy round-seeded varieties will allow picking to start in early June. The wrinkle-seeded peas are less hardy and consequently a little later but their flavour is markedly better. The greenhouse owner can, with a little effort and expertise, get wrinkle-seeded peas podding early by growing them in their initial stages under glass or polythene. Two varieties suitable for this treatment are 'Early Onward* and 'Kelve-don Wonder', neither of which need be staked. They can he sown six to eight weeks earlier than would be normal outdoors. The first thing to be done is to make rectangular troughs from thin planks of wood which have been treated with wood preservative (but on no account use creosote). The troughs should have interior dimensions of about 1 m by 150 mm (3 ft by ft 111) and should he about 150 mm in depth; a 150 mm (ft in) wide plank forms the bottom of the trough and is kept in place by string. Fill the troughs with improved garden soil or, better still, with spent cucumber compost. Sow the seeds somewhat thicker than is normal - that is, two rows with seeds 50 mm (2 in) apart and at a depth ofabout 7s mm {3 in). In the protected conditions germination is usually speedy and the troughs can be transferred to a garden frame when pressure on greenhouse space builds up.

After hardening off, and not before April in the south and May 111 the north, take the troughs to the planting site. Pig out a suitable trench and put the troughs into it. Cut the strings retaining the bottom plank and carefully remove the trough and plank. Rake the soil around the newly planted row to settle the plants: they should now grow satisfactorily having suffered no root disturbance. This system ot growing can be adapted to other crops it space allows.

Runner Beans

I he earliest pickings of outdoor runner beans come from plants raised with some protection and grown as ground beans - that is, plants unsupported by canes and from which the growing tip was pinched when the plant was about 300 mm (12111) tall.

Sowings are made 111 April under cloches, spacing the individual seeds 150 111 in (ft in) apart in the row and later thinning to 2S0 mm (10 in). The soil should have been well manured during the winter months. Alternatively the young plants may be put out as soon as any danger of frost has passed. About one month before the anticipated planting date fill large, shallow boxes with an already used compost mixed with peat to a depth of too mm (4 in). Sow the beans 75111111 (3 in) apart and place the boxes in a warm greenhouse at about 12 C(54 F). As soon as most ot the seedlings have emerged, remove the boxes to the garden frame and give the plants pro-

Early pickings ot peas may be obtained by sowing seeds in (roughs which have removabla boliom boaids Raised in heat, the young plants, still in the trough, are hardened off before they are planted out tcction with a sheet of newspaper on nights when frost is forecast. The plants need to be properly hardened off. When it comes to planting time, prise the plants carefully out of the growing boxes, keeping as much root intact as possible, and plant them 250 mm (10 in) apart in the row. In dry weather it will help them to become established if you spray them lightly for the first tew days with a watering can fitted with a fine rose.

Cambridge Favourtle' strawberries growing in disused fluttering in John Innes compost

Growing Strawberries Plastic Pipe

Strawberries

The earliest home-grown strawberries are produc ed under glass from maiden (one-year-old) plants, Unril recently they were often grown singly in 130 mm (\ m) pots, but it is now more fashionable to grow them 10 purposemade wooden barrels or strawberry urns, which may have an overall height of more than 1 m 0 ft). An alternative, more suitable for the smaller greenhouse, is to grow them 111 a horizontal plastic pipe, about too mm (4 in) in diameter, which is hung from the glazing bars in place of shelving, When grown within the protection o) a greenhouse, strawberries are available several weeks earlier than those grown outdoors. They can be followed by strawberries pot-grown iu a frame, while strawberries grown in the soil under cloches still fruit well in advance ot those without any protection.

Strawberry plants rapidly degenerate w ith virus disease and it is best to buy pot-grown plants which have a certificate of health and have been raised by a specialist grower. Varieties such as 'Cambridge Favourite' give the earliest fruit, and August planting will enable them to establish themselves rapidly. Fill the containers with a potting compost, and provide them with good drainage. The planted containers remain out of doors until February. When brought into a cool greenhouse the plants quickly break into growth and will need regular feeding with a high-potash feed from then onwards. Keep an eye out tor slugs and snails ,is well as aphids. Allow air to circulate freely around the containers, and remove runners as they appear. After they have fruited move the plants outside, trim back the foliage lightly with shears, and retain for fruiting one more year only,

Cambridge Favourtle' strawberries growing in disused fluttering in John Innes compost

Greenhouse Growing Containers

Vines

These are still widely grown under glass, and with careful attention will produce many bunches of grapes a year. However, their heavy canopy ot summer leaf cuts out a great deal of light in the greenhouse, and few crops will grow satisfactorily beneath them at that tune of year. Moreover, in the dormant winter period they prefer really cold conditions, so ventilators need to be left open conditions which most other greenhouse plants will not tolerate. Vines are best planted in border soil just ouiiidi' the greenhouse, and the main stem taken inside through a hole in the wall.

With the increasing interest in grow -iilg grapes, specialist raisers are offering a wider range of varieties, hut the older 'Black Hamburgh* remains one ol the best. Young pot-grown vines are normally planted in the winter months, and the border soil should be enriched with loam and manure. Little or no fruit can he expected until three years after planting. The rods (main steins), ol' which there may be one or two, and the laterat growths are secured by soft string to rows of supporting wires fixed some 250 mm (10 111) below the roof of the greenhouse. Annual winter pruning consists of cutting back the lateral growths to the main stem. Vines can bleed profusely, so they should he fully dormant when this operation is carried out. The bunches of grapes are thinned with special vine scissors, the object being to shape the bunch and remove small, immature fruits that could become mildewed: an old umbrella hung upside down from the wires while you do this job will catçh the small fruits and allow their easy removal from the greenhouse.

A well-trained young vine. Regular tying-m is necessary Vines grow rapidly, and the lateral growths need to be cut back to the main stem every winter After the second sedsun's yruwlli, uul Hit: nidiri item back tu about 1 5 m [5 ft) of new wood

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