At one time, it was customary in large gardens to maintain an orchard house. This was usually a structure in which, fruit trees were grown either with or without heat.
The trees were planted out in borders or grown in pots. In fact, they were often grown by both methods, since then every part of the orchard house could be fully occupied in the production of fruit.
Today things are different and apart from grape vines, it is doubtful whether any gardener would buy a greenhouse solely for the purpose of growing fruit.
Not the least advantage of growing any kind of fruit in the greenhouse is that, it can be brought to perfection before those growing in the open air.
This is especially so if it is possible, to heat the house sufficiently to exclude frost during the flowering period, and for a few weeks afterwards.
Pot grown trees can be plunged outdoors after the fruit has been gathered, and this helps the wood to ripen and form fruit buds for the following year. The span roofed house with a low brick wall forming the base is best for this purpose.
Ideally, it should be sheltered from the north and east, and should be capable of receiving full measure of uninterrupted sunshine. Staging is not required, for the pots can stand on beds of gravel.
Grapes are grown on their own roots, being raised from ‘eyes’ while figs are propagated from cuttings. Other fruit trees grown in pots should be on dwarfing stocks.
For apples, the East Mailing stock IX is reliable and for pears, Angers Quince or Quince ‘A’ are suitable. Peach stocks too are favored by some growers. Peaches themselves are best on Mussel stocks which can also be used for plums.
So long as one is prepared to wait for fruiting, well-grown one-year-old trees can be considered ideal for starting in 18 inches size pots.
Sometimes these young trees have thickish roots, and these are best trimmed back with a sharp knife sufficiently, to enable the root system to be placed in the pot without cramping.
It is important to retain undamaged all the fibrous roots which of course, arise from the thicker roots. Three- to four-year-old trees, planted very early in November are most suitable.
Sometimes they can be bought already in pots from garden centers and nurseries, although they cost a little extra. Alternatively, they are sold removed from the pots in which they were started, so they can be easily repotted.
With these older trees, some root pruning will be necessary to enable the roots to fit easily in the pots.
Although some of the longer top growths can be shortened at the time of potting, any necessary pruning should be done in February when the roots are beginning to grow again.
Plenty of crocks should be placed in the bottom of the pot in the usual way for good drainage, and after putting in some of the compost, the young tree is placed in the pot and the soil carefully worked among the roots.
If, as the soil is added, the base of the pot is tapped sharply on the bench, it will ensure that the soil and roots are in close contact and expel any air pockets.
A potting stick is very useful for firming the soil, although care must be taken not to knock off or bruise any of the fibrous roots.
With the one year or maiden trees, it is best to plunge (sink) them in a bed of weathered coal ashes or something similar, leaving them in the open air for one year to become established.
After the second year, the pots can be taken into the greenhouse each January, where sufficient water with overhead mist sprays should be given from January onwards to encourage early growth.
Older trees can be taken straight into the greenhouse after being potted, and if around 2 feet is allowed between them, it will permit air to circulate freely. Excepting during frosts, the ventilators should be left wide open until the end of January.
During the early part of the year, the soil should be allowed to become almost dry, subsequently give it a good soaking. About the second week in February, the ventilators can be kept closed at night and opened just a little on dull days.
It is important not to allow the temperature to attain more than 46°F at night, or 54°F by day. From this stage onwards, as the flowers begin to open; more heat will be required while regular ventilation will help to set the fruit.
The trees should be encouraged to develop properly by disbudding, which takes the place of summer pruning and they are repotted every second year.
During summer, frequent watering is necessary often as much as twice daily. Some liquid feeding will be beneficial from the time the fruits begin to swell, liquid organic manure being ideal for this purpose.
Routine spraying with insecticides and fungicides is carried out in the same way as for outdoor trees. Apples, pears, plums and cherries are not forced but grown under cooler conditions.
Plums perhaps, appreciate a little more warmth than the others. Apples and pears can be placed outdoors in a warm sunny spot, once the fruit begins to color and mature.
Peaches can be forced to ripen their fruits in May, and if it is possible to have some trees plunged outdoors. These can be brought into the greenhouse once the earlier batch of trees has fruited.
Peaches and nectarines are frequently grown as fan trained specimens placed directly into the greenhouse border.
The following varieties are reliable.
‘Ellisons Orange’, ‘Ribston Pippin’, ‘Cox’s Orange Pippin’ and ‘James Grieve’.
‘Annie Elizabeth’, ‘Newton Wonder’ and ‘Monarch’.
‘Doyenne du Comice’, ‘Louise Bonne of Jersey’, Bon Chretien’.
‘Early Transparent’ Greengage, ‘Victoria’.
Figs grow well in pots especially ‘Brown Turkey’ a Marseilles.’ Leading shoots must be pinched back when they have made up to 1 foot of new growth, and all side shoots stopped two leaves beyond the fruits.
Cherries need selecting with care because of pollination requirements. ‘Early Rivers’, ‘Governor Wood’, ‘Frogmore Early’, and ‘Bigarreau Napoleon’ are suitable for growing together and two or more varieties should ensure fruit.
The best varieties of grapes for indoor culture include:
‘Black Hamburg’, well known for producing good crops with or without heat. It is excellent for growing in pots or very early forcing, and also as a pollinator for some shy fruiting varieties.
The fruits are large, round and blackish, with a sweet flavor and tender flesh.
‘Buckland Sweetwater’, is an early sweet variety requiring similar treatment to ‘Black Hamburg’. The large round berries have a bright green, transparent skin which often shows as amber.
‘Gros Maroc’ is a large thick-skinned grape of a rich reddish-purple color darkening with age. The tender flesh is sweet and juicy, and this is really a first class variety for growing in warmth.
‘Madresfield Court’ is an early Muscat, producing medium sized, tapering bunches of dark purple firm fleshed berries which are tender, juicy and rich.
A free setting variety, it likes just a little warmth. The foliage is an attractive reddish-crimson when it fades.
‘Royal Muscadine’, synonymous with ‘Chasselas de Fontainebleau’ is an early variety, with medium-sized bunches of small golden-yellow berries, which turn a cinnamon shade when exposed to bright sunlight. It is excellent for growing in a sheltered garden or cold greenhouse.